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579 results on '"Fourie J"'

1. Low-cost Monitoring of Energetic Particle Precipitation: Weather Balloon-borne Timepix Measurements During the May 2024 Superstorm

Author

Olifer, L., Manavalan, P., Headrick, D., Palmers, S., Harbarenko, B., Cai, J., Fourie, J., Bauer, O., and Mann, I.

Subjects
Physics - Space Physics
Abstract

Understanding energetic electron precipitation is crucial for accurate space weather modeling and forecasting, impacting the Earth's upper atmosphere and human infrastructure. This study presents a low-cost, low-mass, and low-power solution for high-fidelity analysis of electron precipitation events by measuring the resulting bremsstrahlung X-ray emissions. Specifically, we report on results from the flight of a radiation detector payload based on a silicon pixel read-out Timepix detector technology, and its successful utilization onboard a `burster' weather balloon. We launched this payload during the May 2024 superstorm, capturing high-resolution measurements of both background galactic cosmic ray radiation as well as storm-time energetic electron precipitation. We further developed particle and radiation detection algorithms to separate bremsstrahlung X-rays from other particle species in the pixel-resolved trajectories as seen in the Timepix detector. The measurements revealed a distinctive four-peak structure in X-ray flux, corresponding to periodic four-minute-long bursts of energetic electron precipitation between 21:20 and 21:40 UT. This precipitation was also observed by a riometer station close to the balloon launch path, further validating balloon measurements and the developed X-ray identification algorithm. The clear periodic structure of the measured precipitation is likely caused by modulation of the electron losses from the radiation belt by harmonic Pc5 ULF waves, observed contemporaneously on the ground. The study underscores the potential of compact, low-cost payloads for advancing our understanding of space weather. Specifically, we envision a potential use of such Timepix-based detectors in space science, for example on sounding rockets or nano-, micro-, and small satellite platforms.

Published
2024

2. Selective laser melting of CoCrMo: an evaluation of part density distribution across the build plate

Author

Papworth S.J., Bayode A., Fourie J., and Kloppers CP.

Subjects
Engineering (General). Civil engineering (General), TA1-2040
Abstract

Selective laser melting (SLM) employs the use of powder as the feedstock to manufacture the desired geometries in a layer-by-layer fashion. The part density of manufactured components is one factor used to evaluate part quality since the density has been shown to influence the mechanical properties of SLM components. This study investigated the effect of build location on the part density of selective laser melted CoCrMo. The results showed that the part density varied across the build platform due to the powder packing efficiency. The main role in the density variation is due to the inconsistent powder distribution and packing efficiency across the build plate, negatively affecting the part density.

Published
2022
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3. Numerical Optimization Of The Gating System For An Inlet Valve Casting Made Of Titanium Alloy

Author

Fourie J., Lelito J., Żak P.L., Krajewski P.K., and Wołczyński W.

Subjects
numerical simulation, optimization, porosity, titanium alloys, investment casting, Ti6Al4V alloy, microstructure, Mining engineering. Metallurgy, TN1-997, Materials of engineering and construction. Mechanics of materials, TA401-492
Abstract

The main aim of this work was to numerically investigate and optimize feeding and geometrical parameters to produce inlet valves of Ti6Al4V alloy that are free from defects, especially porosity. It was found that the change of geometry orientation as well as inlet feeder diameter and angle showed distinct relationships between geometric alteration and occurrence of porosity. Alteration in the pouring parameters such as temperature and time had none or only slight effect on occurrence or position of porosity in the valve. It was also found that investigating individual parameters of simple geometry and then utilizing these best fit results in complex geometry yielded beneficial results that would otherwise not be attainable.

Published
2015
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4. Comparative efficacy on dogs of a single topical treatment with fipronil/(S)-methoprene or weekly physiological hygiene shampoos against Ctenocephalides felis in a simulated flea-infested environment

Author

Beugnet F., Fourie J., and Chalvet-Monfray K.

Subjects
dog, flea, simulated infestation, fipronil/(S)-methoprene, shampoo, Infectious and parasitic diseases, RC109-216
Abstract

Flea infestations of pets continue to persist due to the lack of knowledge of flea biology and ecology. It is not unusual that pet owners believe regular hygiene, such as shampooing their dogs can replace regular insecticidal treatment. The objective of this study was to compare in a flea simulated environment, modelling exposure similar to that found in a home, that the use of regular physiological shampoo does not control fleas adequately when compared to a long acting topical formulation. Three groups of six dogs were formed: one untreated control group, one group treated monthly with the topical formulation of fipronil/(S)-methoprene, and a third group treated weekly with a hygiene shampoo. All dogs were infested with adult unfed Ctenocephalides felis fleas (200 ± 5) on Days -28 and -21. Each animal’s sleeping box was fitted with a plastic cup mounted to the inside roof of the box. The sleeping bench of each animal was covered with a carpet to accommodate flea development. The dogs were maintained in their kennels throughout the study. In order to maintain the environmental flea challenge, C. felis pupae (100 ± 5) were placed in the plastic cup in each animal’s sleeping box on Days -14, -7, 0, 7, 14, 21, 28, 35 and 42. The dogs were combed and fleas counted weekly on Days -1, 3, 10, 17, 24, 31, 38, 45, and 51. The fleas were placed immediately back on the dogs. On Day 60, fleas were counted and removed. Flea infestations in the untreated control group at each count averaged between 46.2 and 74.2 fleas throughout the study. The average number of fleas infesting dogs was significantly different (p < 0.05) between the untreated and the two treatment groups and between the two treatment groups at all counts throughout the two months study (Days 3, 10, 17, 24, 31, 38, 45, 51 and 60). The efficacy was never below 99.1% in the fipronil/(S)-methoprene group, and efficacy in the shampoo group was never above 79.2%. Weekly shampooing in treatment group 3 was intentionally delayed after Day 42, to evaluate wether missing a weekly bath would affect the flea population. The Day 48 data indicate that forgetting or delaying a single weekly shampooing resulted in a clear increase in flea numbers and a significant decrease in efficacy from 68.2% to 34.8%. The fipronil(S)/methoprene treatment allowed a continuous control as demonstrated by the high efficacy against fleas, and also the number of flea-free dogs on seven of the nine weekly assessments, in spite of what was essentially a continuous flea challenge model.

Published
2012
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7. The Experiences of Foundation Phase Teachers Regarding Reading Literacy Interventions at an Underperforming School in Gauteng Province

Author

Fourie, J., Sedibe, M., and Muller, M.

Abstract

South Africa's education system has been characterized by various curriculum changes since 1997 given that basic education is a priority of this government and policies have specifically been aimed at improving the overall standard of education in the country. Despite these curriculum changes, the findings of tests such as the Progress in International Reading Literacy Study (PIRLS) of 2006 revealed that South African learners had obtained the lowest overall reading literacy average out of 45 participating educational systems and the South African Consortium for Measuring Educational Quality (SACMEQ) highlighted that the majority of children in South Africa's primary schools are not even reading at the minimal required level. In view of the publicised results of PIRLS 2006 and SAQMEQ 2008, several reading literacy interventions, known as the Foundations for Learning (FFL), Annual National Assessments (ANA) and Gauteng Province Literacy and Mathematics Strategy (GPLMS) have been launched in the past few years to improve literacy and numeracy results in the country. Notwithstanding, the increasing prevalence of low reading literacy results in South Africa raised questions about the effectiveness of interventions intended to improve reading results (in: GDE, Gauteng Primary Literacy Strategy, 2010-2014, Government Printer, Pretoria, 2010). Given the background of this study, the primary aim was to establish the essence of the participant FP teachers' lived experiences regarding the implementation of interventions for reading literacy such as FFL, ANA and GPLMS in order to theorise about the effectiveness of these interventions. The secondary purpose was to add to the body of knowledge concerning FFL, ANA and GPLMS implemented as interventions to improve reading literacy results in South Africa. To achieve these purposes, a phenomenological case study was conducted at one of the 832 identified underperforming schools in Gauteng with eleven Foundation Phase teachers. Three methods were used to collect data namely focus group interviews, non face-to-face interviews and artefacts. The focus group interviews were held in grade context whilst interview forms were given to each of the eleven participants and they were requested to complete it comprehensively in the absence of the researcher. Data from all interviews were corroborated through selected artefacts which were mentioned during the interviews or discovered by the researcher throughout the study. The key findings of this study show that the participants perceived FFL, ANA and GPLMS as mandatory interventions for reading literacy that are unwanted and repetitious. Most importantly the participants deemed ANA as unreliable and unfair whilst FFL and GPLMS were deemed unsuitable for the diverse needs of the learners at this school. In view of the findings, this study concluded that there is limited value in providing mandatory interventions to teachers with the intent of improving the reading literacy results of learners with diverse needs that are contextually bound.

Published
2018
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9. Fruit, vegetable, and legume intake, and cardiovascular disease and deaths in 18 countries (PURE): a prospective cohort study

Author

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, Qing, Deng, Xiaoru, Cheng, Xinye, He, Jian, Li, Juan, Li, Xu, Liu, Bing, Ren, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, 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, Mapanga, R, 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, Li, Wei, Liu, Jiankang, Liu, Xiaoyun, Yin, Lu, Teo, Koon, Anand, Sonia, and Yusuf, Salim

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

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, Qing, Deng, Xiaoru, Cheng, Xinye, He, Jian, Li, Juan, Li, Xu, Liu, Bing, Ren, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, 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, Mapanga, R, 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, and Yusuf, Salim

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

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, Dejesus, J, Elsheikh, W, 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, Qing, Deng, Xiaoru, Cheng, Xinye, He, Jian, Li, Juan, Li, Xu, Liu, Bing, Ren, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, 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, 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, Mapanga, R, Mente, Andrew, Dehghan, Mahshid, Rangarajan, Sumathy, McQueen, Matthew, Dagenais, Gilles, Wielgosz, Andreas, Lear, Scott, Li, Wei, Chen, Hui, 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, and Yusuf, Salim

Published
2017
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12. Availability and affordability of blood pressure-lowering medicines and the effect on blood pressure control in high-income, middle-income, and low-income countries: an analysis of the PURE study data

Author

Yusuf, S, Rangarajan, S, Teo, K K, Chow, C K, O'Donnell, M, Mente, A, Leong, D, Smyth, A, Joseph, P, Islam, S, Zhang, M, Hu, W, Ramasundarahettige, C, Wong, G, Dayal, L, Casanova, A, Dehghan, M, Lewis, G, Aliberti, A, Reyes, A, Zaki, A, Lewis, B, Zhang, B, Agapay, D, Hari, D, Milazzo, E, Ramezani, E, Hussain, F, Shifaly, F, Kay, I, Rimac, J, Swallow, J, Heldman, L, Mushtaha, M(a), Mushtaha, M(o), Trottier, M, Aoucheva, N, Kandy, N, Mackie, P, Solano, R, Chin, S, Ramacham, S, Shahrook, S, Trottier, S, Tongana, T, ElSheikh, W, Lindeman, J, McQueen, M, Hall, K, Keys, J, Wang, X, Keneth, J, Devanath, A, Diaz, R, Orlandini, A, Linetsky, B, Toscanelli, S, Casaccia, G, Maini Cuneo, JM, 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, Dejesus, J, Elsheikh, W, 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, JiaXuan, Bo, Hu, Yi, Sun, Jian, Bo, Xiuwen, Zhao, Xiaohong, Chang, Tao, Chen, Hui, Chen, Qing, Deng, Xiaoru, Cheng, Xinye, He, Jian, Li, Juan, Li, Xu, Liu, Bing, Ren, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, Manlu, Zhu, Fanghong, Lu, Jianfang, Wu, Yindong, Li, Yan, Hou, Liangqing, Zhang, Baoxia, Guo, Xiaoyang, Liao, Shiying, Zhang, BianRongwen, TianXiuzhen, 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, Shankar, K, Kurpad, 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, Różańska, 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, Boström, K Bengtsson, Lindblad, U, Langkilde, P, Gustavsson, A, Andreasson, M, Snällman, M, Wirdemann, L, Pettersson, K, Moberg, E, Yeates, K, Sleeth, J, Kilonzo, K, Oguz, A, Akalin, AAK, Calik, KBT, Imeryuz, N, Temizhan, A, Alphan, E, Gunes, E, Sur, H, Karsidag, K, Gulec, S, Altuntas, Y, 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, Shaibani, H Al, Gharabou, RIM, Youssef, DF, Nawati, AZS, Salah, ZAR Abu, Abdalla, RFE, Shuwaihi, SM Al, Omairi, MA Al, Cadigal, OD, Alejandrino, R.S., Chifamba, J, Gwaunza, L, Terera, G, Mahachi, C, Murambiwa, P, Machiweni, T, Mapanga, R, Attaei, Marjan W, Khatib, Rasha, McKee, Martin, Lear, Scott, Dagenais, Gilles, Igumbor, Ehimario U, AlHabib, Khalid F, Kaur, Manmeet, Kruger, Lanthe, Teo, Koon, Lanas, Fernando, Yusoff, Khalid, Oguz, Aytekin, Gupta, Rajeev, Yusufali, Afzalhussein M, Bahonar, Ahmad, Kutty, Raman, Rosengren, Annika, Mohan, Viswanathan, Avezum, Alvaro, Yusuf, Rita, Szuba, Andrzej, Rangarajan, Sumathy, Chow, Clara, and Yusuf, Salim

Published
2017
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15. The Practice of Oral Medicine in South Africa

Author

Fourie, J and Masenge, A

Subjects
special investigations, scope of practice, oral medicine, oral mucosal disease
Abstract

INTRODUCTION: Oral medicine is a clinical discipline, practiced by periodontists, which concerns itself mostly with the nonsurgical management of oral mucosal diseases. Many of these diseases are rare and the discipline less well known - making it essential to identify the obstacles this discipline faces AIMS AND OBJECTIVES: The purpose of this study was to describe the private and academic practice of Oral Medicine DESIGN AND METHODS: A self-administered, internet-based, questionnaire was distributed to South African periodontists which questioned the clinician's competency, diseases managed, special investigations performed, referral sources, proportional time and monetary distribution of the discipline, and perceived barriers to the practice RESULTS: Twenty-six periodontists completed the questionnaire. In comparison to periodontology and implantology, periodontists generally feel less competent, spend less time on, and receive less money from Oral Medicine. Lack of awareness of the speciality (55.6% - 59.3%) was identified as the biggest constraint, with only 11.2% of referrals received from medical doctors. Immune-mediated diseases (29.3%) and benign neoplasms (26.5%) are managed the most, and surgical biopsies (80.2%) are used most regularly to diagnose oral mucosal disease CONCLUSION: Oral Medicine is still a lesser-known clinical speciality. Despite the heavy burden of HIV-related oral disease and oral mucosal malignancies, this speciality remains underutilised

Published
2022

16. Higher Education Exports in South Africa: A Case Study of Stellenbosch University

Author

du Plessis, E. and Fourie, J.

Abstract

International trade in higher education services is one of the fastest growing tradable service sectors globally. Apart from the positive externalities international students create through knowledge mobility and spill-over, campus diversity, and local community development participation, spending by international students in the host city and immediate surroundings add significantly to local economic growth. The aim of this article is to show, firstly, the relative strong growth of South Africa's higher education exports vis-a-vis other countries. We also find that South Africa has a strong comparative advantage in exporting higher education services. Secondly, we use a pilot questionnaire conducted in 2009 at Stellenbosch University to estimate the economic impact of these students on the local economy. We find that international students contribute between R159 million and R172 million per semester to the local economy, in addition to the positive--but largely unquantifiable--externalities they create. (Contains 12 tables.)

Published
2011

17. Challenges to Internationalisation in African Higher Education

Author

Neale-Shutte, M. and Fourie, J.

Abstract

The paucity of clear, comprehensive and current information about higher education, and internationalisation in African higher education, scratches African countries from contention in both the race within Africa, and the race globally, for quality higher education for the world's mobile students. In addition to a lack of information, other challenges may limit the development of the potential of African higher education, its students, staff, curricula and myriad opportunities for practical experience in many fields. This article explores some of these challenges to internationalisation in African higher education. In addition, Kenya is examined as a case study, and information is provided on the current shape and size of internationalisation in public higher education institutions in Kenya. Developments in internationalisation in Kenyan higher education are contrasted against developments in South African higher education, and the similarities and differences are highlighted. The authors discuss how Africa could strengthen her position through well-functioning cooperative partnerships.

Published
2006

18. A community approach for pathogens and their arthropod vectors (ticks and fleas) in cats of sub-Saharan Africa

Author

Madder, M., Day, M., Schunack, B., Fourie, J., Labuschange, M., van der Westhuizen, W., Johnson, S., Githigia, S.M., Akande, F.A., Nzalawahe, J.S., Tayebwa, D.S., Aschenborn, O., Marcondes, M., Heylen, D., Madder, M., Day, M., Schunack, B., Fourie, J., Labuschange, M., van der Westhuizen, W., Johnson, S., Githigia, S.M., Akande, F.A., Nzalawahe, J.S., Tayebwa, D.S., Aschenborn, O., Marcondes, M., and Heylen, D.

Abstract

Background Arthropod-borne pathogens and their vectors are present throughout Africa. They have been well studied in livestock of sub-Saharan Africa, but poorly studied in companion animals. Given their socioeconomic importance, the African Small Companion Animal Network (AFSCAN), as part of the WSAVA Foundation, initiated a standardized multi-country surveillance study. Methods In six countries (Ghana, Kenya, Nigeria, Tanzania, Uganda, and Namibia) in both rural and urban settings, 160 infested cats were sampled to assess their ectoparasite community (ticks and fleas), as well as the micro-parasite prevalence within those ectoparasites (60 and 118 pools of ticks and fleas, respectively) and blood (276 cats, including 116 non-infested). Results Almost two thirds of all infested cats originated from Tanzania and Kenya. Despite the large macro-geographical variation, no consistent difference was found in ectoparasite diversity and numbers between East and West Africa. Far more flea-infested than tick-infested cats were found. The most dominant ectoparasite was Ctenocephalides felis. Among the ticks, the exophilic Haemaphysalis spp. were the commonest, including species that are not typically linked with companion animals (Haemaphysalis spinulosa and Haemaphysalis elliptica). The most prevalent pathogens found in the blood and fleas were Bartonella henselae and Mycoplasma haemofelis. In the ticks, the dog-associated Hepatozoon canis was most commonly found. A high degree of co-parasitism was found in all countries and habitats. Conclusions Our continent-wide standardized field study highlights the cat’s potential to serve as a reservoir of pathogens that can be transmitted to humans or livestock, especially when cats are expected to become more commonly kept in African villages and towns.

Published
2022

21. Assessing global risk factors for non-fatal injuries from road traffic accidents and falls in adults aged 35–70 years in 17 countries: a cross-sectional analysis of the Prospective Urban Rural Epidemiological (PURE) study

Author

Raina, Parminder, Sohel, Nazmul, Oremus, Mark, Shannon, Harry, Mony, Prem, Kumar, Rajesh, Li, Wei, Wang, Yang, Wang, Xingyu, Yusoff, Khalid, Yusuf, Rita, Iqbal, Romaina, Szuba, Andrzej, Oguz, Aytekin, Rosengren, Annika, Kruger, Annamarie, Chifamba, Jephat, Mohammadifard, Noushin, Darwish, Ebtihal Ahmad, Dagenais, Gilles, Diaz, Rafael, Avezum, Alvaro, Lopez-Jaramillo, Patricio, Seron, Pamela, Rangarajan, Sumathy, Teo, Koon, Yusuf, Salim, Yusuf, S, Rangarajan, S, Teo, KK, Chow, C K, OʼDonnell, M, Mente, A, Leong, D, Smyth, A, Joseph, P, Islam, S, Zhang, M, Hu, W, Wong, G, Manandhar, N, Dehghan, M, Royerr, M, DeJesus, J, Lewis, G, Mackie, P, Farago, L, Kay, I, Agapay, D, Solano, R, Ramacham, S, Kandy, N, Rimac, J, Trottier, S, ElSheikh, W, Mustaha, M, Tongana, T, Aoucheva, N, Swallow, J, Ramezani, E, Lindeman, J, 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, Qing, Deng, Xiaoru, Cheng, Xinye, He, Jian, Li, Juan, Li, Xu, Liu, Bing, Ren, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, 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, PACamacho, 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, S Thakur, J, 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, Iqbal, R, Afridi, A, Khawaja, R, Raza, A, Kazmi, K, Zatonski, W, Szuba, A, Zatonska, K, Ilow, R, Ferus, M, Regulska-Ilow, B, Różańska, D, Wolyniec, M, Kruger, A, Voster, HH, 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, Lindblad, U, Langkilde, P, Gustavsson, A, Andreasson, M, Snällman, M, Wirdemann, L, Pettersson, K, Moberg, E, Oguz, A, Akalin, AAK, Calik, KBT, Imeryuz, N, Temizhan, A, Alphan, E, Gunes, E, Sur, H, Karsidag, K, Gulec, S, Altuntas, Y, Yusufali, AM, Almahmeed, W, Swidan, H, Darwish, EA, Hashemi, ARA, Al-Khaja, N, Muscat-Baron, JM, Ahmed, SH, Mamdouh, TM, Darwish, WM, Abdelmotagali, MHS, Omer Awed, SA, Movahedi, GA, Hussain, F, Shaibani, H Al, Gharabou, RIM, Youssef, DF, Nawati, AZS, Salah, ZAR Abu, Abdalla, RFE, Shuwaihi, SM Al, Omairi, MA Al, Cadigal, OD, Alejandrino, R.S., Chifamba, J, Gwaunza, L, Terera, G, Mahachi, C, Mrambiwa, P, Machiweni, T, and Mapanga, R

Published
2016
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22. EVALUATING THE ACCURACY OF A DIGITAL CORRELATION SYSTEM TO PREDICT THE FATIGUE FAILURE OF ADDITIVELY MANUFACTURED PARTS.

Author

Botha, S., Fourie, J., and Kloppers, C. P.

Subjects
*ELECTRON beam furnaces, *SELECTIVE laser sintering, *DIRECT metal laser sintering, *FATIGUE life, *DIGITAL image correlation, *MANUFACTURING processes, *X-ray computed microtomography
Abstract

Internal defects that occur during the additive manufacturing process of direct metal laser sintering can have a significant influence on the fatigue performance of Ti-6Al-4V additively manufactured parts compared with parts that are made using traditional manufacturing methods. For the adoption of additively manufactured parts in the medical, automotive, and aerospace industries, the expected fatigue life of parts must be predictable and repeatable for successful application. Micro-CT scanning is commonly used to provide insight into the expected fatigue life of parts by examining internal defects that have occurred during melting. However, using a micro-CT for every part in the supply chain is not always feasible, so alternatives must be considered. One approach would be to analyse parts by applying a shortrun fatigue test coupled with a digital image correlation (DIC) system to detect areas on parts where excessive distortion is taking place. This study investigated the level of accuracy that a DIC system could obtain as an alternative non-destructive test to predict where and when a test specimen would fail. To determine whether this alternative was viable, tests were carried out until the specimens failed. The DIC images were analysed at 50% of the fatigue life and at the point just before failure to determine whether the DIC system accurately indicated the strain concentration at the same point where the specimens failed. Experimental data from the study shows that the DIC system could accurately predict the point of failure at the fatigue half-life in only 10% of the test specimens that were investigated. The DIC system was able accurately to predict the point of failure right before failure occurred in only 25% of the test specimens that were investigated. [ABSTRACT FROM AUTHOR]

Published
2023
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24. A community approach of pathogens and their arthropod vectors (ticks and fleas) in dogs of African Sub-Sahara

Author

Heylen, D., Day, M., Schunack, B., Fourie, J., Labuschange, M., Johnson, S., Githigia, S.M., Akande, F.A., Nzalawahe, J.S., Tayebwa, D.S., Aschenborn, O., Marcondes, M., Madder, M., Heylen, D., Day, M., Schunack, B., Fourie, J., Labuschange, M., Johnson, S., Githigia, S.M., Akande, F.A., Nzalawahe, J.S., Tayebwa, D.S., Aschenborn, O., Marcondes, M., and Madder, M.

Abstract

Background Arthropod-borne pathogens and their vectors are present throughout Africa. They have been well-studied in livestock of sub-Saharan Africa, but poorly in companion animals. Given the socio-economic importance of companion animals, the African Small Companion Animal Network (AFSCAN), as part of the WSAVA Foundation, initiated a standardized multi-country surveillance study. Methods Macro-geographic variation in ectoparasite (ticks and fleas) and pathogen communities in dogs was assessed through molecular screening of approximately 100 infested dogs in each of six countries (Ghana, Kenya, Nigeria, Tanzania, Uganda and Namibia), both in rural and urban settings. The most important intrinsic and extrinsic risk factors within the subpopulation of infested dogs were evaluated. Results Despite the large macro-geographic variation in the dogs screened, there was no consistent difference between East and West Africa in terms of the diversity and numbers of ticks. The highest and lowest numbers of ticks were found in Nigeria and Namibia, respectively. Most often, there was a higher diversity of ticks in rural habitats than in urban habitats, although the highest diversity was observed in an urban Uganda setting. With the exception of Namibia, more fleas were collected in rural areas. We identified tick species (including Haemaphysalis spinulosa) as well as zoonotic pathogens (Coxiella burnetti, Trypanosoma spp.) that are not classically associated with companion animals. Rhipicephalus sanguineus was the most abundant tick, with a preference for urban areas. Exophilic ticks, such as Haemaphysalis spp., were more often found in rural areas. Several multi-host ticks occurred in urban areas. For R. sanguineus, housing conditions and additional pets were relevant factors in terms of infestation, while for a rural tick species (Haemaphysalis elliptica), free-roaming dogs were more often infested. Tick occurrence was associated to the use of endoparasiticide, but not to th

Published
2021

27. Characterising retained dormant shoot attributes to support automated cane pruning on Vitis vinifera L. cv. Sauvignon Blanc.

Author

Epee, P.T.M., Schelezki, O.J., Parker, A.K., Trought, M.C.T., Werner, A., Hofmann, R.W., Almond, P., and Fourie, J.

Subjects
VITIS vinifera, SAUVIGNON blanc, FACTORIAL experiment designs, ARTIFICIAL intelligence, GRAPES
Abstract

Background and Aims: The shortage of skilled pruners portends automation as an alternative. To train an Artificial Intelligence (AI) system in cane pruning, the attributes of grapevine dormant shoots were characterised. Methods and Results: Eight attributes of dormant shoots, diameter, length, vertical and horizontal distance, node number, internode length, origin and position relative to bottom fruiting wire, were measured prior to and after pruning. Vine canopies were modified according to a 5 [total node numbers on canes: 10, 20, 30, 40, 50] × 3 [total node numbers on spurs: 1, 2, 3] factorial design. Compared to non‐retained dormant shoots, retained dormant shoots were thicker (9.2 ± 0.07 mm), longer (104.7 ± 0.93 cm), close to the vine trunk (11.4 ± 0.65 cm) and below the bottom fruiting wire (83.2 ± 0.54 cm). Spurs had the shortest horizontal (9.8 ± 0.93 cm) and vertical (77.8 ± 0.7 cm) distance, originating from the vine head, base nodes and first nodes of old canes and old spurs. Modifying the vine canopy via increased node numbers had a significant effect on all retained dormant shoot attributes (P < 0.05) except on the position relative to the bottom fruiting wire. Conclusions: Cane pruning in commercial vineyards is consistent and follows rules based on viticulture knowledge. Retained, non‐retained dormant shoots, canes and spurs exhibit distinct attributes useful in quantifying, assessing and modelling cane pruning. Significance of the Study: Data and knowledge from the research are currently being used in modelling and training AI cane‐pruning algorithms. [ABSTRACT FROM AUTHOR]

Published
2022
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29. Guidelines for Assessment Accommodations 2/e

Author

Fourie J and Fourie J

Subjects
Students with disabilities--Rating of--Handbooks, manuals, etc, Inclusive education--South Africa--Handbooks, manuals, etc, Competency-based educational tests--Handbooks, manuals, etc, Educational tests and measurements--Handbooks, manuals, etc
Abstract

The development of an enabling and socially just learning environment in schools relates to teaching and learning but of equal significance is the assessment of and for learning. Of particular importance is the provision of equitable assessment opportunities for learners who experience physical, sensory and neurological disabilities or specific learning difficulties. Guidelines for assessment accommodations focuses on assessment adaptations and methods of assessment accommodations for learners who experience reading and writing challenges that prevent them from giving a true reflection of their acquired knowledge and skills in classroom tests and examinations. Guidelines for assessment accommodations provides a general and useful framework for assessment practices in an inclusive environment. It discusses the support of learners with language and other difficulties and gives specific techniques for adapting assessments to assist learners.

Published
2022

30. Mzansinomics - Understanding the Basics of the South African Economy

Author

Fourie J, Mohr P and Fourie J, Mohr P

Abstract

What causes economic growth? What determines the price of umqombothi? Why is Eskom a monopoly? Are cryptocurrencies a form of money? Why is South Africa so unequal? Mzansinomics: Understanding the basics of the South African economy introduces economics to a South African audience. It explains the key economic concepts and issues in the news every day – markets, inflation, budget deficits, collusion, inequality, economic growth – in a straightforward, practical and non-technical way. A question-and-answer format, with many examples and updated statistics, exposes South Africa's unique economic challenges and opportunities. The book is useful as a quick reference for seasoned industry professionals, as a text for students who want to obtain a basic understanding of economics without enrolling for a formal mainstream course, and as a resource for those interested in the structure and development of the South African economy. Mzansinomics is the product of two passionate South African economists, Johan Fourie, professor of Economics at Stellenbosch University and Philip Mohr, who was professor of Economics at the University of South Africa for over two decades.

Published
2022

34. Elevated and sustained anti‐feeding effect of Scalibor® deltamethrin collar against the sand fly Phlebotomus perniciosus in dogs confirmed for 1 year following treatment.

Author

Evans, A., Bongiorno, G., Fourie, J. J., Lekouch, N., Bianchi, R., Khoury, C., Thomas, E., Chiummo, R., and Gradoni, L.

Subjects
SAND flies, PHLEBOTOMUS, DELTAMETHRIN, DOGS, FLIES, LEISHMANIA infantum
Abstract

Dogs are reservoir hosts for Leishmania infantum, a protozoan parasite transmitted by phlebotomine sand flies. The anti‐feeding and fast‐killing efficacy of Scalibor® deltamethrin collars against experimental Phlebotomus perniciosus challenges on dogs was determined over 1 year. Two groups of 8 dogs each were fitted with placebo (control) or deltamethrin collars (treated) on Day 0 and exposed to sand flies approximately every 28 days up to Day 364. After each exposure, anti‐feeding and fast‐killing efficacy rates were determined by comparing blood‐fed or live insects, respectively, in the treated vs. the control group. Blood‐fed and live sand flies were significantly less in treated dogs as compared to control dogs at each assessment. The anti‐feeding efficacy rate exceeded 90% except on Day 337 (89%) but increased again (96%) on Day 364. Fast killing efficacy was <74% over the study when considering all flies. However, this value increased cumulatively to 98% when only blood‐fed flies were compared between groups. Scalibor® collars are highly effective at preventing P. perniciosus blood‐feeding and in fast‐killing flies taking a blood meal for up to 1 year after application. These strong and long‐lasting effects are an important strategic component for L. infantum transmission control. [ABSTRACT FROM AUTHOR]

Published
2022
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37. Household, community, sub-national and country-level predictors of primary cooking fuel switching in nine countries from the PURE study

Author

Shupler, Matthew, Hystad, Perry, Gustafson, Paul, Rangarajan, Sumathy, Mushtaha, Maha, Jayachtria, KG, Mony, Prem K, Mohan, Deepa, Kumar, Parthiban, Lakshmi, PVM, Sagar, Vivek, Gupta, Rajeev, Mohan, Indu, Nair, Sanjeev, Varma, Ravi Prasad, Li, Wei, Hu, Bo, You, Kai, Ncube, Tatenda, Ncube, Brian, Chifamba, Jephat, West, Nicola, Yeates, Karen, Iqbal, Romaina, Khawaja, Rehman, Yusuf, Rita, Khan, Afreen, Seron, Pamela, Lanas, Fernando, Lopez-Jaramillo, Patricio, Camacho, Paul A, Puoane, Thandi, Yusuf, Salim, Brauer, Michael, Yusuf, S, Rangarajan, S, Teo, KK, Anand, SS, Chow, CK, O'Donnell, M, Mente, A, Leong, D, Smyth, A, Joseph, P, Duong, M, Kurmi, O, D'Souza, R, Walli-Attaei, M, Balaji, B, Naito, R, Islam, S, Hu, W, Ramasundarahettige, C, Sheridan, P, Bangdiwala, S, Dyal, L, Casanova, A, Dehghan, M, Lewis, G, Agapay, D, Aliberti, A, Aoucheva, N, Arshad, A, Reyes, A, Bideri, B, Buthool, R, Chin, S, Di Marino, M, Frances, R, Gopal, S, Jakymyshn, M, Kandy, N, Kay, I, Lindeman, J, McAlpine, G, McNeice, E, Mushtaha, M, Patel, R, Pattath, D, Ramacham, S, Ramezani, E, Rimac, J, Shifaly, F, Swallow, J, Trottier, M, Trottier, S, Solano, R, Zaki, A, Zhang, B, Zhang, V, Rahman, O, Yusuf, R, Ahmed, SAKS, Choudhury, T, Sintaha, M, Khan, A, Alam, O, Nayeem, N, Mitra, SN, Pasha, F, Lanas, F, Seron, P, Oliveros, MJ, Cazor, F, Palacios, Y, Wei, Li, Lisheng, Liu, Jian, Bo, Bo, Hu, Lu, Yin, Wenhua, Zhao, Hongye, Zhang, Xuan, Jia, Yi, Sun, Xingyu, Wang, Xiuwen, Zhao, Xinye, He, Tao, Chen, Hui, Chen, Xiaohong, Chang, Qing, Deng, Xiaoru, Cheng, Liya, Xie, Zhiguang, Liu, Juan, Li, Jian, Li, Xu, Liu, Bing, Ren, Wei, Wang, Yang, Wang, Jun, Yang, Yi, Zhai, Manlu, Zhu, Fanghong, Lu, Jianfang, Wu, Yindong, Li, Yan, Hou, Liangqing, Zhang, Baoxia, Guo, Xiaoyang, Liao, Shiying, Zhang, BianRongwen, 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, Camacho-Lopez, PA, Otero-Wandurraga, J, Molina, DI, Cure-Cure, C, Perez, M, Hernandez, E, Arcos, E, Narvaez, C, Sotomayor, A, Garcia, H, Sanchez, G, Cotes, F, Rico, A, Duran, M, Torres, C, Mony, P, Vaz, M, Swaminathan, S, Shankar, K, Kurpad, AV, Jayachitra, KG, Kumar, N, Hospital, HAL, Mohan, V, Deepa, M, Parthiban, K, Anitha, M, Hemavathy, S, Rahulashankiruthiyayan, T, Anitha, D, Anjana, RM, Dhanasekar, R, Sureshkumar, S, Sridevi, K, Gupta, R, Panwar, RB, Mohan, I, Rastogi, P, Rastogi, S, Bhargava, R, Kumar, R, Thakur, JS, Patro, B, Mahajan, R, Chaudary, P, Kutty, V Raman, Vijayakumar, K, Ajayan, K, Rajasree, G, Renjini, AR, Deepu, A, Sandhya, B, Asha, S, Soumya, HS, Kaur, M, Sagar, V, Iqbal, R, Khawaja, R, Azam, I, Kazmi, K, Kruger, L, Kruger, A, Bestra, P, Voster, HH, Schutte, AE, 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, Swart, R, Igumbor, E, Tsolekile, L, Ndayi, K, Sanders, D, Naidoo, P, Steyn, N, Peer, N, Mayosi, B, Rayner, B, Lambert, V, Levitt, N, Kolbe-Alexander, T, Ntyintyane, L, Hughes, G, Fourie, J, Muzigaba, M, Xapa, S, Gobile, N, Jwili, B, Ndibaza, K, Egbujie, B, Yeates, K, Oresto, M, West, N, Chifamba, J, Ncube, T, Ncube, B, Chimhete, C, Neya, GK, Manenji, T, Gwaunza, L, Mapara, V, Terera, G, Mahachi, C, Murambiwa, P, Mapanga, R, Chinhara, A, Epidemiolo, Prospective Urban Rural, and Everest

Subjects
010504 meteorology & atmospheric sciences, Air pollution, 010501 environmental sciences, medicine.disease_cause, 01 natural sciences, Agricultural economics, Article, Country level, 11. Sustainability, medicine, Coal, Baseline (configuration management), 0105 earth and related environmental sciences, General Environmental Science, 2. Zero hunger, Kerosene, Renewable Energy, Sustainability and the Environment, business.industry, Multilevel model, 1. No poverty, Public Health, Environmental and Occupational Health, 13. Climate action, Environmental science, Survey data collection, Community setting, business
Abstract

Digital, Introduction. Switching from polluting (e.g. wood, crop waste, coal) to clean (e.g. gas, electricity) cooking fuels can reduce household air pollution exposures and climate-forcing emissions. While studies have evaluated specific interventions and assessed fuel-switching in repeated cross-sectional surveys, the role of different multilevel factors in household fuel switching, outside of interventions and across diverse community settings, is not well understood. Methods. We examined longitudinal survey data from 24 172 households in 177 rural communities across nine countries within the Prospective Urban and Rural Epidemiology study. We assessed household-level primary cooking fuel switching during a median of 10 years of follow up (∼2005–2015). We used hierarchical logistic regression models to examine the relative importance of household, community, sub-national and national-level factors contributing to primary fuel switching. Results. One-half of study households (12 369) reported changing their primary cooking fuels between baseline and follow up surveys. Of these, 61% (7582) switched from polluting (wood, dung, agricultural waste, charcoal, coal, kerosene) to clean (gas, electricity) fuels, 26% (3109) switched between different polluting fuels, 10% (1164) switched from clean to polluting fuels and 3% (522) switched between different clean fuels. Among the 17 830 households using polluting cooking fuels at baseline, household-level factors (e.g. larger household size, higher wealth, higher education level) were most strongly associated with switching from polluting to clean fuels in India; in all other countries, community-level factors (e.g. larger population density in 2010, larger increase in population density between 2005 and 2015) were the strongest predictors of polluting-to-clean fuel switching. Conclusions. The importance of community and sub-national factors relative to household characteristics in determining polluting-to-clean fuel switching varied dramatically across the nine countries examined. This highlights the potential importance of national and other contextual factors in shaping large-scale clean cooking transitions among rural communities in low- and middle-income countries., Ciencias Médicas y de la Salud

Published
2019

41. Measurement of pepsin in porcine gastric juice

Author

Fourie, J, Arnot, RS, Carter, J, Hickman, R, and Terblanche, J

Abstract

The method for measurement of pepsin in human gastric juice as devised by Anson and modified by Berstad has been used for testing pepsin secretion from Heidenhain pouches in pigs. Twenty samples may be analysed at one time with accuracy. Variations in ambient temperature and humidity, and contamination of samples with bile, were found to interfere with the accuracy of the method. There was no change in activity after immediate freezing at -20°C or after storage at -20°C for up to 3 months. After repeated thawing and refreezing on 4 consecutive days, there was a fall in activity on the fourth day only.S. Afr. Med. J., 48, 1873 (1974).

Published
2018

42. VELscope: shedding light on its ideal application

Author

Fourie, J

Subjects
stomatognathic diseases
Abstract

Oral squamous cell carcinoma (OSCC) is a deadly and disfiguring disease. Despite the fact there are readily identifiable precursor lesions and ample opportunity for detection during dental visits, patients continue to succumb to the disease due to late diagnosis. Adjunctive diagnostic aids have been designed to change the natural history of oral cancer by promoting screening practices and allowing for the early identification of OSCC and precursor lesions.' The VELscope is one such device that is available in South Africa, where it is marketed by Inter-Africa Dental. This article will look at the current evidence for the use of the VELscope in different practice scenarios.

Published
2018

43. The Biological Activities of Vitamin D and Its Receptor in Relation to Calcium and Bone Homeostasis, Cancer, Immune and Cardiovascular Systems, Skin Biology, and Oral Health

Author

Khammissa, R. A. G., Fourie, J., Motswaledi, M. H., Ballyram, R., Lemmer, J., and Feller, L.

Subjects
Article Subject
Abstract

Vitamin D plays an important role in calcium homeostasis and bone metabolism, with the capacity to modulate innate and adaptive immune function, cardiovascular function, and proliferation and differentiation of both normal and malignant keratinocytes. 1,25(OH)2D, the biologically active form of vitamin D, exerts most of its functions through the almost universally distributed nuclear vitamin D receptor (VDR). Upon stimulation by 1,25(OH)2D, VDR forms a heterodimer with the retinoid X receptor (RXR). In turn, VDR/RXR binds to DNA sequences termed vitamin D response elements in target genes, regulating gene transcription. In order to exert its biological effects, VDR signalling interacts with other intracellular signalling pathways. In some cases 1,25(OH)2D exerts its biological effects without regulating either gene expression or protein synthesis. Although the regulatory role of vitamin D in many biological processes is well documented, there is not enough evidence to support the therapeutic use of vitamin D supplementation in the prevention or treatment of infectious, immunoinflammatory, or hyperproliferative disorders. In this review we highlight the effects of 1,25(OH)2D on bone and calcium homeostasis, on cancer, and refer to its effects on the cardiovascular and immune systems.

Published
2018
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44. Vitamin D Deficiency as It Relates to Oral Immunity and Chronic Periodontitis

Author

Khammissa, R. A. G., Ballyram, R., Jadwat, Y., Fourie, J., Lemmer, J., and Feller, L.

Subjects
Article Subject
Abstract

The biologically active form of vitamin D, 1,25 dihydroxyvitamin D (1,25(OH)2D) and its receptor, the vitamin D receptor (VDR), play roles in maintaining oral immunity and the integrity of the periodontium. Results of observational cross-sectional clinical studies investigating the association between vitamin D serum level and the incidence and severity of chronic periodontitis indicate that, perhaps owing to the immunomodulatory, anti-inflammatory, and antibacterial properties of 1,25(OH)2 D/VDR signalling, a sufficient serum level of vitamin D is necessary for the maintenance of periodontal health. In cases of established chronic periodontitis, vitamin D supplementation is associated with reduction in the severity of periodontitis. As cross-sectional studies provide only weak evidence for any causal association and therefore are of questionable value, either longitudinal cohort studies, case controlled studies, or randomized control trials are needed to determine whether or not deficiency of vitamin D is a risk factor for chronic periodontitis, and whether or not vitamin D supplementation adjunctive to standard periodontal treatment is in any way beneficial. In this article, we discuss the relationship between vitamin D, oral immunity and periodontal disease and review the rationale for using vitamin D supplementation to help maintain periodontal health and as an adjunct to standard periodontal treatment.

Published
2018
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45. Evaluation of efavirenz on neurochemical and oxidative stress markers and addictive-like behaviours in rats

Author

Fourie, J., Möller Wolmarans, M., Dr, Harvey, B.H., Prof, 21247250 - Möller Wolmarans, Marisa (Supervisor), 11083417 - Harvey, Brian Herbert (Supervisor), Möller-Wolmarans, M., Dr, and 21247250 - Möller-Wolmarans, Marisa (Supervisor)

Subjects
whoonga, monoamines, nyaope, oxidative stress, Efavirenz, conditioned place preference, drug abuse
Abstract

MSc (Pharmacology), North-West University, Potchefstroom Campus HIV positive patients treated with the antiretroviral (ARV) drug efavirenz have been observed to experience various neuropsychiatric symptoms including insomnia, dizziness, somnolence, vivid and abnormal dreams and thoughts and manic episodes, clearly indicating central nervous system (CNS) effects. Moreover, recent news reports in South Africa describe people recreationally using efavirenz by crushing and smoking this ARV drug in a mixture of drugs known as "Nyaope" or "Whoonga". Other than efavirenz as the main constituent, this mixture is known to contain marijuana, milk powder, rat poison, amongst others. The abuse of this drug places tremendous pressure on the Department of Health and endangers the lives of people in need of ARV treatment. A previous preclinical study suggests that the effects of efavirenz are in line with that of lysergic acid diethylamide (LSD), mediated by a partial agonist effect on the serotonin (5-HT) - 2A receptor subtype, the primary binding site for drugs of abuse known as the hallucinogens. Drugs of abuse are known to alter the behaviour and neurochemistry of the abuser and some studies also suggest alterations in the anti-oxidant system of the body, linked to monoamine alterations, in this instance, dopamine (DA), 5-HT and noradrenaline. Animal models enable research to screen for alterations in the above-mentioned indicators and to determine the underlying mechanism through which a drug may elicit its abuse potential and related addictive-like effects. A well-known behavioural test to assess rewarding properties of drugs is the conditioned place preference (CPP) test in which the motivational or aversive properties of a drug serves as an unconditioned stimulus that is continuously paired with an environment. Through Pavlovian principles, this leads to an association of the previously neutral environment with the properties of the drug. Rewarding or addictive drugs are known to significantly increase the time spent in the drug-paired compartment after conditioning. Various other behavioural screening tests such as the sucrose preference test (SPT) may indicate whether a drug interacts with the reward pathways under the control of DAergic signalling, leading to changes in sucrose consumption (as hedonic measure). Moreover, the psychomotor stimulant theory suggests that drugs of abuse induce hyper-locomotion (in the open field test (OFT)) in animals, which is considered a valuable test to screen for drugs of abuse. Furthermore, this test may be of value in supporting the outcome of other tests (such as the CPP test) in which locomotion plays an imperative role. This study aimed to assess the addictive-like properties of efavirenz after sub-acute (6 days) and sub-chronic (14 days) exposure in rats. The present study (ethical approval no: NWU - 00267- 16- S5) used a total of 84 male Sprague Dawley rats (randomly allocated to 7 groups of rats with 12 rats per drug exposure group), bred and housed in the DST/NWU PCDDP Vivarium. The sub-acute paradigm exposed 5 groups of rats to i.p injections of either 5, 10 or 20 mg/kg/d efavirenz, 1 mg/kg/d methamphetamine (MA) (as a positive control) or vehicle in order to establish the most rewarding dosage of efavirenz. CPP, sucrose preference and locomotor activity were assessed in the sub-chronic study, evaluating the effects of efavirenz on reward (CPP), anhedonic manifestations over time (SPT) and locomotion (OFT). In the sub-acute study, MA was compared to a vehicle in order to validate the CPP paradigm under our laboratory conditions. The sub-chronic study was conducted using the most rewarding dose of efavirenz as determined in the sub-acute phase (5mg/kg/d alternate days x 14 days). Furthermore, quantification of frontal cortical, striatal and hippocampal DA, 5-HT, and their respective metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-Hydroxyindoleacetic acid (5-HIAA) as well as NA was performed in the sub-chronic efavirenz exposure study, using a high-performance liquid chromatography system with electrochemical detection (HPLC-EC). Regional brain lipid peroxidation and plasma superoxide dismutase (SOD) levels were also assessed after sub-chronic exposure to efavirenz, utilizing ELISA kits. One-way ANOVA with Dunnett's post hoc test or unpaired student t-tests were applied for statistical analyses with p < 0.05 deemed significant. In the sub-acute study, 5 mg/kg efavirenz induced a significant increase in the time spent in the drug-paired compartment compared to the control group in the CPP test. These results were comparable to the rewarding effects of MA in the same test. Efavirenz at 10 mg/kg showed no changes, while 20 mg/kg showed a significant decrease in the time spent in the drug-paired compartment in comparison to the control group. In contrast to data described in the CPP test, no changes in locomotion or sucrose preference were observed. Neurochemical analyses in the sub-chronically exposed efavirenz animals indicated a significant increase in frontal cortical DA and 5-HT levels whilst 5 HIAA levels were significantly lower compared to vehicle exposed animals. DA and 5-HT turnover was significantly decreased in animals exposed to sub-chronic efavirenz compared to a vehicle control. Striatal DA, 5-HT and NA were increased while DOPAC levels and DA turnover was decreased in these animals compared to the vehicle control. Hippocampal DA, DOPAC, 5-HIAA and 5-HT turnover was significantly decreased whereas DA turnover rate was significantly increased in animals exposed to efavirenz compared to the vehicle control. Peripheral (plasma) SOD levels were significantly increased in efavirenz treated animals, while regional brain lipid peroxidation was significantly elevated in the DA rich areas (frontal cortex and striatum), compared to their vehicle control. The findings in the sub-acute and sub-chronic study demonstrate a significant dose dependant rewarding effect of efavirenz in rats (in a validated CPP paradigm under our laboratory conditions), with lower doses being most effective and higher doses eliciting aversive responses. The unaltered preference for sucrose after sub-chronic efavirenz exposure further supports the outcomes that the lower doses are rewarding since no anhedonic behaviour manifested over the period of treatment. Unaltered locomotion suggests that sub-chronic efavirenz does not elicit its effects through the same striatal-mediated mechanism as do many other drugs of abuse but supports the outcome in the CPP test. Moreover, this implies that performance in the CPP was not a result of undue effects of the drug or condition on the mobility of the animals. The findings obtained in the sub-chronic study confirm that efavirenz alters regional brain DA, 5-HT, NA and lipid peroxidation as well as peripheral SOD levels. This animal study has significant relevance in elucidating the possible mechanism through which efavirenz induces a rewarding effect, which in turn may underlie its abuse potential. Masters

Published
2018

50. Selection of Grass and Broadleaf Crops as Catch Crops where Winery Wastewater is Used for Irrigation: A Review.

Author

Fourie, J. C., Howell, C. L., and Masekwana, N.

Subjects
*CATCH crops, *SEWAGE, *WINE industry, *CROPS, *WINTER grain, *COVER crops
Abstract

Winery wastewater contains high levels of elements such as sodium, phosphorus, potassium, as well as chemical oxygen demand, sodium adsorption ratio and pH. This may raise concerns regarding the pollution of the surrounding environment. Environmentally friendly methods such as recycling, i.e. treatment and re-use, where treated or partially treated and diluted wastewater is used for irrigation of agricultural crops, are essential. Irrigation with winery wastewater, which is rich in nutrients, can be beneficial to overall soil fertility as an alternative to conventional fertilizers. However, long-term applications of wastewater may have a negative effect on soil physicochemical properties. A selection of crops with nutrient interception abilities, preferably for salts, may be ideal for the removal of excess elements from the soil whilst reducing leaching and excess run off. The use of perennial grasses, annual winter growing grains and winter growing broadleaf nitrogen-fixing annuals as winter cover crops in the South African wine industry has been extensively documented but their use as summer catch crops intercepting elements applied via wastewater irrigation has not yet been well researched. [ABSTRACT FROM AUTHOR]

Published
2021
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