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1. Deeply virtual Compton scattering cross section at high Bjorken $x_B$

Author

Georges, F., Rashad, M. N. H., Stefanko, A., Dlamini, M., Karki, B., Ali, S. F., Lin, P-J., Ko, H-S, Israel, N., Adikaram, D., Ahmed, Z., Albataineh, H., Aljawrneh, B., Allada, K., Allison, S., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Biswas, D., Brash, E., Bulumulla, D., Campbell, J., Camsonne, A., Carmignotto, M., Castellano, J., Chen, C., Chen, J-P., Chetry, T., Christy, M. E., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J. C., Dusa, S. Covrig, Crowe, B., Danagoulian, S., Danley, T., De Persio, F., Deconinck, W., Defurne, M., Desnault, C., Di, D., Duer, M., Duran, B., Ent, R., Fanelli, C., Franklin, G., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Glamazdin, O., Gnanvo, K., Gray, V. M., Gu, C., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holmstrom, T., Horn, T., Huang, Y., Huber, G. M., Hyde, C., Ibrahim, H., Jen, C-M., Jin, K., Jones, M., Kabir, A., Keppel, C., Khachatryan, V., King, P. M., Li, S., Li, W. B., Liu, J., Liu, H., Liyanage, A., Magee, J., Malace, S., Mammei, J., Markowitz, P., McClellan, E., Mazouz, M., Meddi, F., Meekins, D., Mesik, K., Michaels, R., Mkrtchyan, A., Montgomery, R., Camacho, C. Muñoz, Myers, L. S., Nadel-Turonski, P., Nazeer, S. J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obretch, O. F., Ou, L., Palatchi, C., Pandey, B., Park, S., Park, K., Peng, C., Pomatsalyuk, R., Pooser, E., Puckett, A. J. R., Punjabi, V., Quinn, B., Rahman, S., Reimer, P. E., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N. H., Schmookler, B., Shabestari, M. H., Shahinyan, A., Sirca, S., Smith, G. R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Su, T., Subedi, A., Sulkosky, V., Sun, A., Thorne, L., Tian, Y., Ton, N., Tortorici, F., Trotta, R., Urciuoli, G. M., Voutier, E., Waidyawansa, B., Wang, Y., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z., Yero, C., Zhang, J., Zhao, Y., and Zhu, P.

Subjects
High Energy Physics - Phenomenology, High Energy Physics - Experiment, Nuclear Experiment
Abstract

We report high-precision measurements of the Deeply Virtual Compton Scattering (DVCS) cross section at high values of the Bjorken variable $x_B$. DVCS is sensitive to the Generalized Parton Distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton Form Factors (CFFs) of the nucleon as a function of $x_B$, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.

Published
2022
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2. Form Factors and Two-Photon Exchange in High-Energy Elastic Electron-Proton Scattering

Author

Christy, M. E., Gautam, T., Ou, L., Schmookler, B., Wang, Y., Adikaram, D., Ahmed, Z., Albataineh, H., Ali, S. F., Aljawrneh, B., Allada, K., Allison, S. L., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Arrington, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Bhatt, H., Bhetuwal, D., Biswas, D., Brash, E., Bulumulla, D., Camacho, C. M., Campbell, J., Camsonne, A., Carmignotto, M., Castellanos, J., Chen, C., Chen, J-P., Chetry, T., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J. C., Dusa, S. Covrig, Crowe, B., Danagoulian, S., Danley, T., Deconinck, W., Defurne, M., Desnault, C., Di, D., Dlamini, M., Duer, M., Duran, B., Ent, R., Fanelli, C., Fuchey, E., Gal, C., Gaskell, D., Georges, F., Gilad, S., Glamazdin, O., Gnanvo, K., Gramolin, A. V., Gray, V. M., Gu, C., Habarakada, A., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Hernandez, A. V., Henry, W., Higinbotham, D. W., Holmstrom, T., Horn, T., Huang, Y., Huber, G. M., Hyde, C., Ibrahim, H., Israel, N., Jen, C-M., Jin, K., Jones, M., Kabir, A., Karki, B., Keppel, C., Khachatryan, V., King, P. M., Li, S., Li, W., Liu, H., Liu, J., Liyanage, A. H., Mack, D., Magee, J., Malace, S., Mammei, J., Markowitz, P., Mayilyan, S., McClellan, E., Meddi, F., Meekins, D., Mesick, K., Michaels, R., Mkrtchyan, A., Moffit, B., Montgomery, R., Myers, L. S., Nadel-Turonski, P., Nazeer, S. J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obrecht, R. F., Ohanyan, K., Palatchi, C., Pandey, B., Park, K., Park, S., Peng, C., Persio, F. D., Pomatsalyuk, R., Pooser, E., Puckett, A. J. R., Punjabi, V., Quinn, B., Rahman, S., Rashad, M. N. H., Riordan, S., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N. H., Shabestari, M. H., Shahinyan, A., Sirca, S., Smith, G. R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Stefanko, A., Su, T., Subedi, A., Sulkosky, V., Sun, A., Tan, Y., Thorne, L., Ton, N., Tortorici, F., Trotta, R., Uniyal, R., Urciuoli, G. M., Voutier, E., Waidyawansa, B., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z. H., Yero, C., Zhang, J., Zhao, Y. X., and Zhu, P.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q$^2$) up to 15.75~\gevsq. Combined with existing data, these provide an improved extraction of the proton magnetic form factor at high Q$^2$ and double the range over which a longitudinal/transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q$^2$ and attributed to hard two-photon exchange (TPE) effects, extending to 8~(GeV/c)$^2$ the range of Q$^2$ for which a discrepancy is established at $>$95\% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q$^2$., Comment: 7 pages, 2 figures

Published
2021
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3. Deep exclusive electroproduction of $\pi^0$ at high $Q^2$ in the quark valence regime

Author

The Jefferson Lab Hall A Collaboration, Dlamini, M., Karki, B., Ali, S. F., Lin, P-J., Georges, F., Ko, H-S, Israel, N., Rashad, M. N. H., Stefanko, A., Adikaram, D., Ahmed, Z., Albataineh, H., Aljawrneh, B., Allada, K., Allison, S., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Biswas, D., Brash, E., Bulumulla, D., Campbell, J., Camsonne, A., Carmignotto, M., Castellano, J., Chen, C., Chen, J-P., Chetry, T., Christy, M. E., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J. C., Dusa, S. Covrig, Crowe, B., Danagoulian, S., Danley, T., De Persio, F., Deconinck, W., Defurne, M., Desnault, C., Di, D., Duer, M., Duran, B., Ent, R., Fanelli, C., Franklin, G., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Glamazdin, O., Gnanvo, K., Gray, V. M., Gu, C., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holmstrom, T., Horn, T., Huang, Y., Huber, G. M., Hyde, C., Ibrahim, H., Jen, C-M., Jin, K., Jones, M., Kabir, A., Keppel, C., Khachatryan, V., King, P. M., Li, S., Li, W., Liu, J., Liu, H., Liyanage, A., Magee, J., Malace, S., Mammei, J., Markowitz, P., McClellan, E., Meddi, F., Meekins, D., Mesik, K., Michaels, R., Mkrtchyan, A., Montgomery, R., Camacho, C. Munoz, Myers, L. S., Nadel-Turonski, P., Nazeer, S. J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obretch, O. F., Ou, L., Palatchi, C., Pandey, B., Park, S., Park, K., Peng, C., Pomatsalyuk, R., Pooser, E., Puckett, A. J. R., Punjabi, V., Quinn, B., Rahman, S., Reimer, P. E., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N. H., Schmookler, B., Shabestari, M. H., Shahinyan, A., Sirca, S., Smith, G. R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Su, T., Subedi, A., Sulkosky, V., Sun, A., Thorne, L., Tian, Y., Ton, N., Tortorici, F., Trotta, R., Urciuoli, G. M., Voutier, E., Waidyawansa, B., Wang, Y., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z., Yero, C., Zhang, J., Zhao, Y., and Zhu, P.

Subjects
High Energy Physics - Experiment, Nuclear Experiment
Abstract

We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of $x_B$ (0.36, 0.48 and 0.60) and $Q^2$ (3.1 to 8.4 GeV$^2$) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions $d\sigma_L/dt+\epsilon d\sigma_T/dt$, $d\sigma_{TT}/dt$, $d\sigma_{LT}/dt$ and $d\sigma_{LT'}/dt$ are extracted as a function of the proton momentum transfer $t-t_{min}$. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross-section throughout this kinematic range. The data are well described by calculations based on transversity Generalized Parton Distributions coupled to a helicity flip Distribution Amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.

Published
2020
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4. Automatic scoring of apnea and hypopnea events using blood oxygen saturation signals

Author

Rolon, R. E., Gareis, I. E., Larrateguy, L. D., Di Persia, L. E., Spies, R. D., and Rufiner, H. L.

Subjects
Electrical Engineering and Systems Science - Signal Processing, Computer Science - Computers and Society
Abstract

The obstructive sleep apnea-hypopnea (OSAH) syndrome is a very common and frequently undiagnosed sleep disorder. It is characterized by repeated events of partial (hypopnea) or total (apnea) obstruction of the upper airway while sleeping. This study makes use of a previously developed method called DAS-KSVD for multiclass structured dictionary learning to automatically detect individual events of apnea and hypopnea using only blood oxygen saturation signals. The method uses a combined discriminant measure which is capable of efficiently quantifying the degree of discriminability of each one of the atoms in a dictionary. DAS-KSVD was applied to detect and classify apnea and hypopnea events from signals obtained from the Sleep Heart Health Study database. For moderate to severe OSAH screening, a receiver operating characteristic curve analysis of the results shows an area under the curve of 0.957 and diagnostic sensitivity and specificity of 87.56% and 88.32%, respectively. These results represent improvements as compared to most state-of-the-art procedures. Hence, the method could be used for screening OSAH syndrome more reliably and conveniently, using only a pulse oximeter., Comment: 15 pages, 7 figures

Published
2020

5. A multi-class structured dictionary learning method using discriminant atom selection

Author

Rolón, R. E., Di Persia, L. E., Spies, R. D., and Rufiner, H. L.

Subjects
Computer Science - Machine Learning, Computer Science - Computer Vision and Pattern Recognition, Statistics - Machine Learning
Abstract

In the last decade, traditional dictionary learning methods have been successfully applied to various pattern classification tasks. Although these methods produce sparse representations of signals which are robust against distortions and missing data, such representations quite often turn out to be unsuitable if the final objective is signal classification. In order to overcome or at least to attenuate such a weakness, several new methods which incorporate discriminative information into sparse-inducing models have emerged in recent years. In particular, methods for discriminative dictionary learning have shown to be more accurate (in terms of signal classification) than the traditional ones, which are only focused on minimizing the total representation error. In this work, we present both a novel multi-class discriminative measure and an innovative dictionary learning method. For a given dictionary, this new measure, which takes into account not only when a particular atom is used for representing signals coming from a certain class and the magnitude of its corresponding representation coefficient, but also the effect that such an atom has in the total representation error, is capable of efficiently quantifying the degree of discriminability of each one of the atoms. On the other hand, the new dictionary construction method yields dictionaries which are highly suitable for multi-class classification tasks. Our method was tested with a widely used database for handwritten digit recognition and compared with three state-of-the-art classification methods. The results show that our method significantly outperforms the other three achieving good recognition rates and additionally, reducing the computational cost of the classifier., Comment: 18 pages, 8 figures and 3 tables

Published
2018

10. Learn-teach-learn: Evaluating a South African near-peer teaching programme

Author

Spies, R, Lee, H, Esack, I, Hollamby, R., and Viljoen, C

Abstract

Background. Near-peer teaching (NPT) programmes may benefit both student learners (SLs) and near-peer tutors (NTs). However, data evaluating NPT programmes in developing countries such as South Africa are lacking.Objectives. To evaluate the efficacy of an NPT programme in improving the knowledge and confidence of SLs and NTs, and to evaluate student perceptions of the NPT programme.Methods. An NPT programme in which clinical year students provided tutorials to pre-clinical year students was developed. Participants completed a knowledge-assessing multiple-choice questionnaire (MCQ) and a confidence-assessing questionnaire at commencement and conclusion of the programme. Participants also completed an evaluation at the end of the programme.Results. For 38 SLs, the median MCQ score improved from 58.9% at baseline to 78.6% at completion of the programme (p

Published
2022

11. Introducing the youth residential rehabilitation service: An operational and experiential overview of a psychosocial residential support option for young people experiencing mental health challenges

Author

Spies, R, Ennals, P, Egan, R, Hemus, P, Gonzales, R, Droppert, K, Tidhar, M, McMullan, S, Lessing, K, Wood, T, Bride, R, Bendall, S, Simmons, M, Spies, R, Ennals, P, Egan, R, Hemus, P, Gonzales, R, Droppert, K, Tidhar, M, McMullan, S, Lessing, K, Wood, T, Bride, R, Bendall, S, and Simmons, M

Abstract

AIM: A range of residential supports is available for young people experiencing mental health challenges. One Australian example is the Youth Residential Rehabilitation Service, which provides up to 12 months of intensive psychosocial support in a residential setting to young people aged 16-25 experiencing serious mental health challenges. This paper aimed to add to the scant literature on these services, describing the experiences of young people and staff members across the duration of a stay. METHODS: This study drew on collaborative autoethnography to engage and centre the direct lived experience of young people who had lived, and staff who had worked, in a Youth Residential Rehabilitation Service. RESULTS: We identified three phases that young people typically journey through during their stay at the service. The Arriving phase was marked by appropriate referrals, a warm welcome, a period of settling in and the development of trusting relationships. The Discovering phase saw young people identifying and enacting their strengths, hopes and values. Community connections were a focus of the Continuing phase as lives after service exit were envisioned and created. CONCLUSIONS: Drawing on collaborative autoethnography methods represents one approach to amplify the voice of young people in service design and evaluation. This paper richly described some of the possibilities and complexities of the Youth Residential Rehabilitation Service experience, which can be used to inform the service's pacing and structure of support.

Published
2022

12. Co-producing to understand what matters to young people living in youth residential rehabilitation services

Author

Ennals, P, Lessing, K, Spies, R, Egan, R, Hemus, P, Droppert, K, Tidhar, M, Wood, T, van Dijk, C, Bride, R, Asche, A, Bendall, S, Simmons, M, Ennals, P, Lessing, K, Spies, R, Egan, R, Hemus, P, Droppert, K, Tidhar, M, Wood, T, van Dijk, C, Bride, R, Asche, A, Bendall, S, and Simmons, M

Abstract

AIM: Residential group care is an important service for vulnerable young people experiencing mental health, substance abuse and/or behavioural challenges. Yet little is written about specific models and their outcomes, especially from the perspectives of the young people who use these services. This project aimed to explore what matters to young people living in a 12-month voluntary residential program for young people aged 16-25. METHODS: This participatory action research study was co-produced with Youth Residential Rehabilitation Service residents and staff as co-researchers. A steering group comprising residents, staff and researchers oversaw all research stages. 18 young people and 17 staff members participated in either individual or group interviews to discuss what was important in Youth Residential Rehabilitation Services. Data analysis drew on grounded theory techniques; subsequent codes and themes were refined in the steering group. RESULTS: We identified the 'change work' that young people were expected to do, and the milieu factors that created a supportive environment. As young people were figuring out their directions and learning new skills, they needed to be understood as the developing expert of their own lives. Real relationships with staff and other young people created a culture of belonging, safety and feeling known. These findings are metaphorically captured in the image of an egg. CONCLUSIONS: Our study highlights that real relationships between all Youth Residential Rehabilitation Service community members are central to creating the atmosphere of safety and belonging that enables healing and self-development to occur.

Published
2022

13. Form Factors and Two-Photon Exchange in High-Energy Elastic Electron-Proton Scattering

Author

Christy, M. E., primary, Gautam, T., additional, Ou, L., additional, Schmookler, B., additional, Wang, Y., additional, Adikaram, D., additional, Ahmed, Z., additional, Albataineh, H., additional, Ali, S. F., additional, Aljawrneh, B., additional, Allada, K., additional, Allison, S. L., additional, Alsalmi, S., additional, Androic, D., additional, Aniol, K., additional, Annand, J., additional, Arrington, J., additional, Atac, H., additional, Averett, T., additional, Ayerbe Gayoso, C., additional, Bai, X., additional, Bane, J., additional, Barcus, S., additional, Bartlett, K., additional, Bellini, V., additional, Beminiwattha, R., additional, Bericic, J., additional, Bhatt, H., additional, Bhetuwal, D., additional, Biswas, D., additional, Brash, E., additional, Bulumulla, D., additional, Camacho, C. M., additional, Campbell, J., additional, Camsonne, A., additional, Carmignotto, M., additional, Castellanos, J., additional, Chen, C., additional, Chen, J-P., additional, Chetry, T., additional, Cisbani, E., additional, Clary, B., additional, Cohen, E., additional, Compton, N., additional, Cornejo, J. C., additional, Covrig Dusa, S., additional, Crowe, B., additional, Danagoulian, S., additional, Danley, T., additional, Deconinck, W., additional, Defurne, M., additional, Desnault, C., additional, Di, D., additional, Dlamini, M., additional, Duer, M., additional, Duran, B., additional, Ent, R., additional, Fanelli, C., additional, Fuchey, E., additional, Gal, C., additional, Gaskell, D., additional, Georges, F., additional, Gilad, S., additional, Glamazdin, O., additional, Gnanvo, K., additional, Gramolin, A. V., additional, Gray, V. M., additional, Gu, C., additional, Habarakada, A., additional, Hague, T., additional, Hamad, G., additional, Hamilton, D., additional, Hamilton, K., additional, Hansen, O., additional, Hauenstein, F., additional, Hernandez, A. V., additional, Henry, W., additional, Higinbotham, D. W., additional, Holmstrom, T., additional, Horn, T., additional, Huang, Y., additional, Huber, G. M., additional, Hyde, C., additional, Ibrahim, H., additional, Israel, N., additional, Jen, C-M., additional, Jin, K., additional, Jones, M., additional, Kabir, A., additional, Karki, B., additional, Keppel, C., additional, Khachatryan, V., additional, King, P. M., additional, Li, S., additional, Li, W., additional, Liu, H., additional, Liu, J., additional, Liyanage, A. H., additional, Mack, D., additional, Magee, J., additional, Malace, S., additional, Mammei, J., additional, Markowitz, P., additional, Mayilyan, S., additional, McClellan, E., additional, Meddi, F., additional, Meekins, D., additional, Mesick, K., additional, Michaels, R., additional, Mkrtchyan, A., additional, Moffit, B., additional, Montgomery, R., additional, Myers, L. S., additional, Nadel-Turonski, P., additional, Nazeer, S. J., additional, Nelyubin, V., additional, Nguyen, D., additional, Nuruzzaman, N., additional, Nycz, M., additional, Obrecht, R. F., additional, Ohanyan, K., additional, Palatchi, C., additional, Pandey, B., additional, Park, K., additional, Park, S., additional, Peng, C., additional, Persio, F. D., additional, Pomatsalyuk, R., additional, Pooser, E., additional, Puckett, A. J. R., additional, Punjabi, V., additional, Quinn, B., additional, Rahman, S., additional, Rashad, M. N. H., additional, Reimer, P. E., additional, Riordan, S., additional, Roche, J., additional, Sapkota, I., additional, Sarty, A., additional, Sawatzky, B., additional, Saylor, N. H., additional, Shabestari, M. H., additional, Shahinyan, A., additional, Širca, S., additional, Smith, G. R., additional, Sooriyaarachchilage, S., additional, Sparveris, N., additional, Spies, R., additional, Stefanko, A., additional, Su, T., additional, Subedi, A., additional, Sulkosky, V., additional, Sun, A., additional, Tan, Y., additional, Thorne, L., additional, Ton, N., additional, Tortorici, F., additional, Trotta, R., additional, Uniyal, R., additional, Urciuoli, G. M., additional, Voutier, E., additional, Waidyawansa, B., additional, Wojtsekhowski, B., additional, Wood, S., additional, Yan, X., additional, Ye, L., additional, Ye, Z. H., additional, Yero, C., additional, Zhang, J., additional, Zhao, Y. X., additional, and Zhu, P., additional

Published
2022
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14. Deeply virtual Compton scattering cross section at high Bjorken x_{B}

Author

Georges, F, Rashad, M. N. H., Stefanko, A, Dlamini, M, Karki, B, Ali, S. F., Lin, P-J, Ko, H-S, Israel, N, Adikaram, D, Ahmed, Z, Albataineh, H, Aljawrneh, B, Allada, K, Allison, S, Alsalmi, S, Androic, D, Aniol, K, Annand, John, Atac, H, Averett, T, Ayerbe Gayoso, C, Bai, X, Bane, J, Barcus, S, Bartlett, K, Bellini, V, Beminiwattha, R, Bericic, J, Biswas, D, Brash, E, Bulumulla, D, Campbell, J, Camsonne, A, Carmignotto, M, Castellano, J, Chen, C, Chen, J-P, Chetry, T, Christy, M. E., Cisbani, E, Clary, B, Cohen, E, Compton, N, Cornejo, J. C., Covrig Dusa, S, Crowe, B, Danagoulian, S, Danley, T, De Persio, F, Deconinck, W, Defurne, M, Desnault, C, Di, D, Duer, M, Duran, B, Ent, R, Fanelli, C, Franklin, G, Fuchey, E, Gal, C, Gaskell, D, Gautam, T, Glamazdin, O, Gnanvo, K, Gray, V. M., Gu, C, Hague, T, Hamad, G, Hamilton, David, Hamilton, K., Hansen, O, Hauenstein, F, Henry, W, Higinbotham, D. W., Holmstrom, T, Horn, T, Huang, Y, Huber, G. M., Hyde, C. E., Ibrahim, H, Jen, C-M, Jin, K, Jones, M, Kabir, A, Keppel, C, Khachatryan, V, King, P. M., Li, S, Li, W. B., Liu, J, Liu, H, Liyanage, A, Magee, J, Malace, S, Mammei, J, Markowitz, P, McClellan, E, Mazouz, M, Meddi, F, Meekins, D, Mesik, K, Michaels, R, Mkrtchyan, A, Montgomery, Rachel, Muñoz Camacho, C, Myers, L. S., Nadel-Turonski, P, Nazeer, S. J., Nelyubin, V, Nguyen, D, Nuruzzaman, N, Nycz, M, Obretch, O. F., Ou, L, Palatchi, C, Pandey, B, Park, S, Park, K, Peng, C, Pomatsalyuk, R, Pooser, E, Puckett, A. J. R., Punjabi, V, Quinn, B, Rahman, S, Reimer, P. E., Roche, J, Sapkota, I, Sarty, A, Sawatzky, B, Saylor, N. H., Schmookler, B, Shabestari, M. H., Shahinyan, A, Sirca, S, Smith, G. R., Sooriyaarachchilage, S, Sparveris, N, Spies, R, Su, T, Subedi, A, Sulkosky, V, Sun, A, Thorne, L, Tian, Y, Ton, N, Tortorici, F, Trotta, R, Urciuoli, G. M., Voutier, E, Waidyawansa, B, Wang, Y, Wojtsekhowski, B, Wood, S, Yan, X, Ye, L, Ye, Z, Yero, C, Zhang, J, Zhao, Y, Zhu, P, and Jefferson Lab Hall A Collaboration

Abstract

We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton form factors (CFFs) of the nucleon as a function of x_{B}, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.

Published
2022

15. Deep Exclusive Electroproduction of π0 at High Q2 in the Quark Valence Regime

Author

The Jefferson Lab Hall A Collaboration, Dlamini, M., Karki, B., Ali, S. F., Lin, P-J., Georges, F., Ko, H-S, Israel, N., Rashad, M. N. H., Stefanko, A., Adikaram, D., Ahmed, Z., Albataineh, H., Aljawrneh, B., Allada, K., Allison, S., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Biswas, D., Brash, E., Bulumulla, D., Campbell, J., Camsonne, A., Carmignotto, M., Castellano, J., Chen, C., Chen, J-P., Chetry, T., Christy, M. E., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J. C., Dusa, S. Covrig, Crowe, B., Danagoulian, S., Danley, T., De Persio, F., Deconinck, W., Defurne, M., Desnault, C., Di, D., Duer, M., Duran, B., Ent, R., Fanelli, C., Franklin, G., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Glamazdin, O., Gnanvo, K., Gray, V. M., Gu, C., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holmstrom, T., Horn, T., Huang, Y., Huber, G. M., Hyde, C., Ibrahim, H., Jen, C-M., Jin, K., Jones, M., Kabir, A., Keppel, C., Khachatryan, V., King, P. M., Li, S., Li, W., Liu, J., Liu, H., Liyanage, A., Magee, J., Malace, S., Mammei, J., Markowitz, P., McClellan, E., Meddi, F., Meekins, D., Mesik, K., Michaels, R., Mkrtchyan, A., Montgomery, R., Camacho, C. Munoz, Myers, L. S., Nadel-Turonski, P., Nazeer, S. J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obretch, O. F., Ou, L., Palatchi, C., Pandey, B., Park, S., Park, K., Peng, C., Pomatsalyuk, R., Pooser, E., Puckett, A. J. R., Punjabi, V., Quinn, B., Rahman, S., Reimer, P. E., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N. H., Schmookler, B., Shabestari, M. H., Shahinyan, A., Sirca, S., Smith, G. R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Su, T., Subedi, A., Sulkosky, V., Sun, A., Thorne, L., Tian, Y., Ton, N., Tortorici, F., Trotta, R., Urciuoli, G. M., Voutier, E., Waidyawansa, B., Wang, Y., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z., Yero, C., Zhang, J., Zhao, Y., Zhu, P., Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Jefferson Lab Hall A

Subjects
[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], momentum transfer dependence, helicity, High Energy Physics - Experiment, pi: distribution amplitude, generalized parton distribution: transversity, kinematics, pi0: electroproduction, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], quark: valence, polarization: transverse, High Energy Physics::Experiment, p: structure function, Nuclear Experiment, experimental results, photon: virtual, Jefferson Lab
Abstract

International audience; We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of xB (0.36, 0.48, and 0.60) and Q2 (3.1 to 8.4 GeV2) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσT/dt+εdσL/dt, dσTT/dt, dσLT/dt, and dσLT′/dt are extracted as a function of the proton momentum transfer t-tmin. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.

Published
2021
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16. Concept and development of an interactive tool for trial recruitment planning and management

Author

Spies, R., Siegfried, N., Myers-Franchi, Bronwyn, Grobbelaar, S.S., Spies, R., Siegfried, N., Myers-Franchi, Bronwyn, and Grobbelaar, S.S.

Abstract

Background: Predicting and monitoring recruitment in large, complex trials is essential to ensure appropriate resource management and budgeting. In a novel partnership between clinical trial investigators of the South African Medical Research Council and industrial engineers from the Stellenbosch University Health Systems Engineering and Innovation Hub, we developed a trial recruitment tool (TRT). The objective of the tool is to serve as a computerised decisions-support system to aid the planning and management phases of the trial recruitment process. Method: The specific requirements of the TRT were determined in several workshops between the partners. A Poisson process simulation model was formulated and incorporated in the TRT to predict the recruitment duration. The assumptions underlying the model were made in consultation with the trial team at the start of the project and were deemed reasonable. Real-world data extracted from a current cluster trial, Project MIND, based in 24 sites in South Africa was used to verify the simulation model and to develop the monitoring component of the TRT. Results: The TRT comprises a planning and monitoring component. The planning component generates different trial scenarios for predicted trial recruitment duration based on user inputs, e.g. number of sites, initiation delays. The monitoring component uses and analyses the data retrieved from the trial management information system to generate different levels of information, displayed visually on an interactive, user-friendly dashboard. Users can analyse the results at trial or site level, changing input parameters to see the resultant effect on the duration of trial recruitment. Conclusion: This TRT is an easy-to-use tool that assists in the management of the trial recruitment process. The TRT has potential to expedite improved management of clinical trials by providing the appropriate information needed for the planning and monitoring of the trial recruitment phase. This T

Published
2021

17. Indiscriminate friendliness in foster children: Associations with attachment security, foster parents' sensitivity, and child inhibitory control

Author

Schoemaker, N.K., Vermeer, H.J., Juffer, F., Spies, R., Ee, E. van, Maras, A., Alink, L.R.A., Schoemaker, N.K., Vermeer, H.J., Juffer, F., Spies, R., Ee, E. van, Maras, A., and Alink, L.R.A.

Abstract

Contains fulltext : 226861.pdf (publisher's version ) (Open Access), Indiscriminate friendliness (IF) is atypical behavior often seen in postinstitutionalized and foster children. The current exploratory study examined the associations of children's attachment security, parental sensitivity, and child inhibitory control with reported and observed IF in 60 family-reared, never-institutionalized foster children. IF was measured with a parent-report questionnaire (Indiscriminate Friendliness Questionnaire) and an observational measure (adapted version of the Stranger at the Door procedure; Bucharest Early Intervention Project). Attachment security and inhibitory control were related to reported IF (i.e., a secure attachment and poor inhibitory control were associated with higher levels of IF), but parental sensitivity was not. No associations were found between observed IF and attachment security, parental sensitivity, or inhibitory control. Thus, foster children with a secure attachment relationship may be more prone to socially interact with others including strangers, whereas better inhibitory control may serve as a buffer against IF but these results were found for reported IF only. More research is needed to gain more knowledge about different measures, other possible correlates, and underlying mechanisms of IF.

Published
2020

18. A multi-class structured dictionary learning method using discriminant atom selection

Author

Rol��n, R. E., Di Persia, L. E., Spies, R. D., and Rufiner, H. L.

Subjects
FOS: Computer and information sciences, Computer Science - Machine Learning, Statistics - Machine Learning, Computer Vision and Pattern Recognition (cs.CV), Computer Science - Computer Vision and Pattern Recognition, Machine Learning (stat.ML), Machine Learning (cs.LG)
Abstract

In the last decade, traditional dictionary learning methods have been successfully applied to various pattern classification tasks. Although these methods produce sparse representations of signals which are robust against distortions and missing data, such representations quite often turn out to be unsuitable if the final objective is signal classification. In order to overcome or at least to attenuate such a weakness, several new methods which incorporate discriminative information into sparse-inducing models have emerged in recent years. In particular, methods for discriminative dictionary learning have shown to be more accurate (in terms of signal classification) than the traditional ones, which are only focused on minimizing the total representation error. In this work, we present both a novel multi-class discriminative measure and an innovative dictionary learning method. For a given dictionary, this new measure, which takes into account not only when a particular atom is used for representing signals coming from a certain class and the magnitude of its corresponding representation coefficient, but also the effect that such an atom has in the total representation error, is capable of efficiently quantifying the degree of discriminability of each one of the atoms. On the other hand, the new dictionary construction method yields dictionaries which are highly suitable for multi-class classification tasks. Our method was tested with a widely used database for handwritten digit recognition and compared with three state-of-the-art classification methods. The results show that our method significantly outperforms the other three achieving good recognition rates and additionally, reducing the computational cost of the classifier., 18 pages, 8 figures and 3 tables

Published
2018

22. Learn-teach-learn: Evaluating a South African near-peer teaching programme.

Author

Spies, R., Lee, H., Esack, I., Hollamby, R., and Viljoen, C.

Subjects
*PEER teaching, *STUDENT attitudes, *MEDICAL students, *EDUCATIONAL standards, *CONFIDENCE, DEVELOPING countries
Abstract

Background. Near-peer teaching (NPT) programmes may benefit both student learners (SLs) and near-peer tutors (NTs). However, data evaluating NPT programmes in developing countries such as South Africa are lacking. Objectives. To evaluate the efficacy of an NPT programme in improving the knowledge and confidence of SLs and NTs, and to evaluate student perceptions of the NPT programme. Methods. An NPT programme in which clinical year students provided tutorials to pre-clinical year students was developed. Participants completed a knowledge-assessing multiple-choice questionnaire (MCQ) and a confidence-assessing questionnaire at commencement and conclusion of the programme. Participants also completed an evaluation at the end of the programme. Results. For 38 SLs, the median MCQ score improved from 58.9% at baseline to 78.6% at completion of the programme (p<0.001; d=1.3). The mean overall confidence score improved from 2.6/5 at baseline to 3.6/5 at completion (p<0.001; d=1.3). All SLs agreed that the NPT programme was a useful addition to the standard curriculum and that they would recommend the programme to other students at developmental level. The effect of the NPT programme was less pronounced for the 16 NTs, with median MCQ scores of 87.5% and 89.3% at baseline and completion of the programme, respectively (p=0.179; d=0.4). The mean overall confidence score improved from 3.8/5 at baseline to 4.2/5 at completion (p=0.004; d=1). Ninety-four percent of NTs agreed that their role as NTs reinforced their existing knowledge. Conclusion. NPT programmes may improve the knowledge and confidence of SLs, while consolidating the knowledge of NTs. The NTP programme was well received by medical students. In resource-limited settings, the effectiveness and acceptability of NPT make it an attractive adjunct to traditional teaching. [ABSTRACT FROM AUTHOR]

Published
2021
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23. HIV/Aids and psychosis: needs, challenges and support of affected mothers

Author

Spies, R., Sterkenburg, P.S., van Rensburg, E, Schuengel, C., Spies, R., Sterkenburg, P.S., van Rensburg, E, and Schuengel, C.

Abstract

Little is known about parenting in the context of HIV and psychosis, two co-existing conditions affecting many mothers in South Africa. In this study a mixed methods approach was used to firstly do qualitative investigation of the illness and parenting experiences of a case group of mothers living with HIV/AIDS and psychosis (n = 41). Secondly, the support networks of this group are compared with a control group of mothers with HIV/AIDS without psychosis (n = 44). Integrating qualitative and quantitative data highlight the emotional and physical disruption experienced by the case group that contribute to dysfunctional mother–child interactions. This experience may be detrimental to the child’s well-being and formation of attachment relationships. Healthy support networks may buffer these adversities. The availability of support figures is similar between the groups, but the case group has less spousal support. Paranoia associated with the case group predicted fewer support figures, thus emphasizing the vulnerability of this group of mothers and children.

Published
2017
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24. Attachment relationships of preschool-aged children of mothers with HIV and HIV-related psychosis

Author

12835471 - Spies, Abraham Gerhardus, 10194118 - Van Rensburg, Esmé, Spies, R., Sterkenburg, P.S., Van Rensburg, E., Schuengel, C., 12835471 - Spies, Abraham Gerhardus, 10194118 - Van Rensburg, Esmé, Spies, R., Sterkenburg, P.S., Van Rensburg, E., and Schuengel, C.

Abstract

Children from mothers with HIV-related psychosis are frequently raised in challenging contexts, yet the extent to which these children grow up in insecure or disordered attachment relationships is unknown. Using the Strange Situation Procedure the distribution of attachment relationships of children from mothers with HIV and psychosis (n = 45) was compared with children from mothers with HIV without psychosis (n = 41). No significant differences in the distributions were found between the two groups and attachment was not associated with specific psychotic symptomatology. Security of attachment was associated with more people providing the mother with emotional support, but only in the psychosis group. Disordered attachment (24%) was more often found in the total sample than in studies with other normal and high risk populations. Recommendations were made for future research about factors facilitating resilience in the children and on interventions increasing emotional support for affected mothers

Published
2016

26. Inheriting Mary Ainsworth and the Strange Situation: Questions of Legacy, Authority, and Methodology for Contemporary Developmental Attachment Researchers

Author

Ruan Spies, Robbie Duschinsky, Spies, Ruan [0000-0002-8303-2176], Apollo - University of Cambridge Repository, and Spies, R [0000-0002-8303-2176]

Subjects
Underpinning, Psychoanalysis, Ainsworth, attachment theory, General Arts and Humanities, media_common.quotation_subject, General Social Sciences, Social Sciences, methodology, legacy, AZ20-999, Attachment theory, Strange situation, inheritance, History of scholarship and learning. The humanities, 47 Language, Communication and Culture, Sociology, Inheritance, media_common, 44 Human Society, Original Research
Abstract

Mary Ainsworth’s legacy continues to shape the social and developmental sciences well after her death. The Ainsworth Strange Situation Procedure has, for decades, not only provided the underpinning methodology of attachment research, but also the frame of reference for theory. This has produced conditions where, as in psychoanalysis, debates about the future of the paradigm also entail a struggle to claim and negotiate the legacy of a founding figure. To date, historians have only looked at attachment research up to the 1980s. Interviews with 15 leading contemporary attachment researchers revealed Ainsworth’s importance to later research, but also laid bare the challenges of claiming her inheritance in responding to the current challenges facing this area of research.

Published
2021
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27. Assessing the predictive strength of a Clinical/Counselling Psychology Master's degree selection process

Author

Derwin, Robyn, Spies, R., Coetzee, H., and 24838616 - Fosso-Kankeu, Elvis (Supervisor)

Subjects
education
Abstract

MA (Clinical Psychology), North-West University, Potchefstroom Campus This study aimed to investigate the validity of a selection process for a clinical and counselling psychology master’s degree at an undisclosed university in South Africa. Assessing the validity of such a process is essential, as this process selects candidates who, after completing their degree, will provide mental health resources to communities in SA. Applications for these degrees far outweigh the limited number of positions available, thus leading to a vast number of individuals who are not accepted into these programmes and can therefore not register as clinical or counselling psychologists. It is therefore imperative to select candidates who possess the necessary skills and characteristics required of a “good” psychologist. The selection process at the participating university included six different selection activities, each assessing different skills sets and attributes of the candidates. Together, these activities are set to evaluate the overall potential of the candidate to become a “good” psychologist. The activities include two interviews, a metaphors activity, a research task, a case-study activity, and a problem-solving activity. This study defined a “good psychologist” as one who possesses the relevant attributes, skills and characteristics required to develop strong working alliances with clients in psychotherapy – an important contributing facet of therapeutic change within the client. The study’s aim was achieved by completing correlation and regression analyses between the six selection activities, the six course modules, and the course average in the student’s M1 year. Results showed significant positive regressions between the metaphors activity, child psychopathology, and theory of psychological interventions modules, between the research task and neuropsychology, between the psychopharmacology and psychopathology modules, and between the problem-solving activity and the course average. The case study activity negatively predicted the ethics and practical work and applied and community psychology modules. The conclusion was that the selection process can be considered valid, as the skills assessed for most of the selection activities positively correlated and predicted the skills required to succeed both academically in the M1 year and as a practising psychologist. This indicates that this selection process selects candidates who are considered “good students” with the potential to be “good psychologists”. However, the case study activity required further investigation, as the skills that are purportedly assessed should correlate and positively predict the ethics and practical work module, which was not the case. Masters

Published
2021

28. Infanticide and its relationship with postpartum psychosis : a critical interpretive synthesis

Author

Jansen van Rensburg, Nicole, Spies, R., Malan, Linda, 10091130 - Malan, Linda (Supervisor), and Malan, L.

Abstract

MA (Clinical Psychology), North-West University, Potchefstroom Campus Homicide is the cause of death in one in five deaths related to injury globally in children aged younger than five years (Child Trends, 2015). Infanticide is defined as the homicide of an infant within its first year of life (Ellonen, Kaarianeh, Lethi, & Aaltonen, 2015). The most likely perpetrators of infanticide are the biological mothers of the infants (Stockl et al., 2017). Infanticide in developed countries occurs at an estimated rate of 2.1 to 6.9 per 100 000 live births (Abrahams et al., 2016). South Africa’s infanticide rate is estimated at 28.9 per 100 000 live births, more than double that of the global estimates (Abrahams et al., 2016). Postpartum psychosis is currently considered a ‘rare’ phenomenon in the literature, occurring in approximately one to two per 1000 births (Doucet, Letoutneau, & Robertson-Blackmore, 2011). Postpartum psychosis is considered as a psychiatric emergency (Barnes & Brown, 2016). The most noticeable symptoms of postpartum psychosis include delusions, hallucinations, and disorganised behaviour (Stewart et al., 2003). Infanticide is one of the well-known risk factors for women suffering from postpartum psychosis (Spinelli, 2009). The current literature on the phenomenon of infanticide within the context of postpartum psychosis is predominantly either medically informed or informed by legislation. The study aimed to synthesise the available literature on the phenomenon of infanticide within the context of postpartum psychosis. The method used to achieve this was Critical interpretive synthesis (CIS), as coined by Dixon-Woods et al. (2006). The study further aimed to shift its focus to the environmental aspects involved in the outcome of infanticide within the context of postpartum psychosis, as well as the chosen method of inflicting death. A synthesis of the literature from a different perspective added to the existing body of knowledge in a new and meaningful manner. This could possibly lead to greater awareness on the phenomenon and inform further research. An electronic search of the literature using the EBSCO Discovery Service was used. Ultimately, 51 sources were considered of which 15 were included in the final sample. Sources were included based on their quality and ability to answer the research questions. Non-peer reviewed studies and studies without the potential to adequately address the research questions were excluded. All sources under consideration were independently reviewed by the primary and co-reviewer in terms of their title and abstract. The studies were then examined in full text to finalise inclusion or exclusion independently by the reviewers. The reviewers ultimately agreed to include the final 15 sources. The reviewers critically appraised the sources using the two-pronged approach as suggested by Dixon-Woods et al. (2006). The reviewers then proceeded to the data analysis phase and ultimately constructed a list of initial themes which emerged from the literature. The initial themes became synthetic constructs which assisted with the exploration and discussion of the phenomenon of infanticide within the context of postpartum psychosis. In addition, due to the natural critique arising from CIS (Dixon-Woods et al., 2006), a critical reflection of the current body of literature formed part of the study. The first synthetic construct involved the prior psychiatric history of the perpetrator as well as prior psychiatric care. The second construct involved the demographics of the perpetrator including age, marital status, and employment. The third synthetic construct involved the perceptions on motherhood e.g., wanting to become a mother and planning pregnancy, as well as those perceptions resulting from the individuals in their environment such as the women being superior caretakers. An additional construct involved the victims: the synthesis found that victims were often aged between three and 11 months, which had implications for diagnostic considerations, i.e., that there are often multiple victims including older biological children and that victims are commonly killed using hands. The following synthetic construct was based on the presence of warning behaviour before infanticide was committed. The study also reflected on the current state of literature. The study indicated that most research on the topic is outdated, with a mean publication date of 2000. In addition, the current available literature is heavily informed by the medical or legislative disciplines. Furthermore, the manner in which both the concepts of infanticide and postpartum psychosis is described and understood is reflective of society’s view on motherhood and how mothers ‘should’ be. Lastly, the study discusses the implications of describing the phenomenon of psychotic infanticide as rare. Masters

Published
2019

29. Exploring the athletic-ideal body image and eating disturbances in a selected South African sample

Author

Williams, Lindi, Naidoo, D., Spies, R., and 12835471 - Spies, Abraham Gerhardus (Supervisor)

Subjects
Balance, Body ideal, Body ideal internalization, Thin-ideal, Body dissatisfaction, Obsessive exercise, education, Athletic-ideal, Eating disturbances, Obligatory exercise, Internalization
Abstract

PhD (Psychology), North-West University, Potchefstroom Campus The athletic-ideal and associated behaviours have not yet been adequately addressed in current literature. For the past two years researchers focused on the thin-ideal internalization. This researcher explored the extent to which the athletic-ideal, body image, and eating disturbances affected on a selected South African sample. This research study is presented in three manuscripts. The aim of the first manuscript was to explore the relationship between the athletic-ideal internalization and its association with clinical aspects, such as body dissatisfaction, eating disorders, and maladaptive exercise behaviours. This quantitative cross-sectional study included on-campus female students (N = 476) from the three campuses of the North-West University (NWU) in South Africa. Participants completed four online self-report questionnaires (The Sociocultural Attitudes Towards Appearance Scale-4; The MBSRQ Appearance Scale; The Obligatory Exercise Questionnaire; The Eating Attitudes Test). Findings suggested that the athletic-ideal is gaining popularity. Furthermore, significant relationships between athletic-internalization, obligatory exercise and dieting were evident, yet yielded a poor relationship with body dissatisfaction. As with other studies, it appears that the athletic-ideal is less harmful to body dissatisfaction and dieting than the thin-ideal. A stronger association between obligatory exercise was found with the athletic-ideal than with the thin-ideal. The aim of the second manuscript was to explore the subjective experiences of individuals that have internalized this ideal and investigated the behaviours associated with reaching the athletic-ideal. This qualitative study followed a phenomenological approach to explore nine participants’ perceptions of their athletic-ideal internalization. Data from semistructured interviews were analyzed using the Interpretative Phenomenological Analysis methodology. Results indicated a prominent theme of balance with regard to eating and exercise. In this study, it was evident that participants’ pursuits of the athletic-ideal body are more focused on health-related goals than on appearance-related ideals. Following the guidelines of a healthy lifestyle and a balanced exercise routine appears to act as protective factors against body image disturbances, maladaptive eating and compulsive exercise. In the third manuscript the aim was to explore how practicing psychologists in clinical practice make sense of the athletic-ideal. This study explored how they classify, diagnose and treat their patients who have an athletic-ideal internalization with pathological associated behaviour. The qualitative study followed a grounded theory approach to explore nine psychologists’ understanding of the athletic-ideal and subsequent implications for diagnostic classification and treatment. Results indicated that, if the athletic-pursuit includes balance and flexibility, the pursuit can lead to positive psychological and physical benefits. When the inverse is present, obsessive-compulsive and rigidity in the pursuit start to affect psychological, physiological, social and occupational functioning. In the absence of clear, evidence-based diagnostic classification guidelines for a pathological pursuit of the athletic-ideal, diagnostic classifications of eating disorders, muscle dysmorphia and associated depressive and anxiety disorders are often used. Psychologists follow an individualized form of treatment that includes cognitive behaviour, family systems and psychodynamic approaches. Research on the athletic-ideal internalization in clinical practice is still in its early stages and peer-reviewed evidence is needed to establish diagnostic criteria and course descriptions of a pathological pursuit of the athletic-ideal. In conclusion, the study primarily contributed to the exploration of the athletic-ideal and its associated outcomes in a South-African sample. Doctoral

Published
2019

30. Psychometric properties of the PID-5-BF in an undergraduate sample of South African university students

Author

Venema, H., Spies, R., Dr., and De Beer, L., Prof.

Subjects
Discriminant validity, Construct validity, Personality disorder, Convergent validity, PID-5-BF, NEO-PI-R
Abstract

MA (Clinical Psychology), North-West University, Potchefstroom Campus Assessments are regularly used amongst clinicians within Psychology, yet many are deemed too time-consuming and expensive. The Personality Inventory for DSM-5 Brief Form (PID-5-BF) was developed to measure maladaptive personality traits (Negative Affect, Detachment, Antagonism, Disinhibition, and Psychoticism), based on the "hybrid model" for personality disorders included in the DSM 5 Section III. Literature indicates that reliability and validity for the PID-5-BF has been established in other countries. We explored these psychometric properties within a South African population using the NEO Personality Inventory Revised and MINI Subscale K: Psychotic disorders and mood disorder with psychotic features, as measures for comparison. Our results indicated support for the PID-5-BF with sufficient reliability, convergent and discriminant validity. More research is needed on the PID-5-BF, especially in South Africa, but our findings indicate it to be a promising assessment tool that could greatly benefit clinicians in the mental health sector. Masters

Published
2019

31. Older people's experiences of the Grandparent-Grandchild (GP-GC) relationship in the contemporary South African context

Author

Spangenberg, M., Spies, R., Dr, Van Aardt, J.M., and 20556888 - Van Aardt, Janine Magdalene (Supervisor)

Subjects
Cohesion, experiences, grandparents, intergenerational relationships
Abstract

MA (Clinical Psychology), North-West University, Potchefstroom Campus Rapid demographical changes are evident worldwide owing to the significant increase in the number of older people. Seven-point eight percent of South Africa's total population consists of people ages 60 years and older, bringing about multi-generational bonds or intergenerational relationships (i.e. Grandparent-Grandchild relationship). In the African context, grandparents play a major role in child-fostering and the care of grandchildren. Black South African grandparents perceive their grandchildren to be disrespectful and rude, while their grandchildren perceive their grandparents to be rigid and negative. Afrikaans- and English-speaking young adults describe older people as an integral part of society and have high regard for their contributions, past and present. This underpins the researcher's endeavour to explore Afrikaans- and English-speaking older people's experiences embedded in the GP-GC relationship. The aim of the study was to explore, Afrikaans- and English-speaking older persons' experiences of the Grandparent-Grandchild relationship (GP-GC), in an effort to provide insight into the relational aspects of the GP-GC relationship in the South African context. A qualitative approach was followed together with a qualitative descriptive research design to explore older people's experiences in-depth. In-depth interviews were conducted with 21 selected participants. The proposed research study required analysis of the collected interviews by means of thematic analysis, as the researcher endeavoured to explore the GP-GC relationship entrenched in the very nature of relationships shared between Afrikaans- and English-speaking generations. Masters

Published
2018

32. Adult attachment theory and Rorschach Inkblot method: a systematic literature review

Author

Zizi, P., Spies, R., Dr, Vosloo, C., and 11821094 - Vosloo, Cristel (Supervisor)

Subjects
systematic literature review, Rorschach Inkblot
Abstract

MA (Clinical Psychology), North-West University, Potchefstroom Campus This study systematically reviewed the association between the Rorschach Inkblot Method and attachment theory, to investigate whether empirical findings have found if responses from the Rorschach Inkblot Method can provide information on constructs of attachment theory. The motivation for this study is based on the fact that, although both the Rorschach Inkblot Method and attachment theory have been empirically explored separately, as well as regarding the various links between the two subjects, varying links between the two have been indicated (Shaver, Segal, Berant & Mikulincer, 2005). Therefore, the review aimed to find the most consistent, reliable and valid links between the Rorschach Inkblot Method and attachment theory, and it systematically and critically reviewed studies on the Rorschach Inkblot Method that measure the constructs of the attachment relationship or attachment representations (Shaver et al., 2005). The following objectives were set in order to reach the aim of the study which was to determine which variables of the Rorschach are associated with adult attachment constructs: Firstly, to critically review available literature concerning the association between the Rorschach Inkblot Method and attachment theory; and secondly, to critically review studies on the Rorschach Inkblot Method measure variables, that measure constructs of the attachment relationship or attachment representations. The question that guided this research was: How are variables in the Rorschach Inkblot Method associated with adult attachment theory constructs? Literature, specifically published between 1974 and 2015, relevant to the aim and question of the study was retrieved, while ignoring irrelevant literature. Data collection involved a search strategy, which entailed the selection of specific key or search words or terms; proposed resources such as databases and manual searches, as well as the formulation of inclusion and exclusion criteria. The researcher formulated the selection criteria to retrieve studies relevant to the research question in order to ensure that the research is comprehensive and specific, while excluding irrelevant research material. The first author, using the research question as well as the inclusion and exclusion criteria, systematically searched and selected relevant literature titles, followed by the selection of relevant abstracts from the selected titles and lastly the relevant full texts for the study. An independent reviewer followed the same steps. The lists of the selected titles, abstracts and texts were compared for consensus. Through critical appraisal, the selected articles were assessed for quality and relevance. In total, 17 Rorschach variables were identified in the nine studies with varying strengths in their associations with adult attachment. The most significant variables identified as linking with attachment were the texture response variable, the oral response and the Rorschach oral dependency. The studies' sample sizes ranged from single case studies to a medium sample size (n=224). A limitation of the studies was the fact that they all made use of Exner's Comprehensive System, which is not the latest Rorschach interpretation tool; in addition, all the studies used attachment assessment tools, which were self-report measures (Cassella & Viglione, 2009; Iwasa & Ogawa, 2010). Assessments of attachment are currently done through the use of the AAI and the AAP, which require specialized training that is expensive. The Rorschach is more accessible and versatile, and does not have cultural barriers and has been used in South Africa (Moletsane, 2004); therefore finding valid Rorschach variables that correlate with attachment constructs will have incredible implications on the practice and policy of Psychology. Masters

Published
2018

33. Spatial Analysis of Drug-Susceptible and Multidrug-Resistant Cases of Tuberculosis, Ho Chi Minh City, Vietnam, 2020-2023.

Author

Spies R, Hong HN, Trieu PP, Lan LK, Lan K, Hue NN, Huong NTL, Thao TTLN, Quang NL, Anh TDD, Vinh TV, Ha DTM, Dat PT, Hai NP, Van LH, Thwaites GE, Thuong NTT, Watson JA, and Walker TM

Subjects
Male, Humans, Vietnam epidemiology, Asia, Spatial Analysis, Tuberculosis, Tuberculosis, Multidrug-Resistant epidemiology
Abstract

We characterized the spatial distribution of drug-susceptible (DS) and multidrug-resistant (MDR) tuberculosis (TB) cases in Ho Chi Minh City, Vietnam, a major metropolis in southeastern Asia, and explored demographic and socioeconomic factors associated with local TB burden. Hot spots of DS and MDR TB incidence were observed in the central parts of Ho Chi Minh City, and substantial heterogeneity was observed across wards. Positive spatial autocorrelation was observed for both DS TB and MDR TB. Ward-level TB incidence was associated with HIV prevalence and the male proportion of the population. No ward-level demographic and socioeconomic indicators were associated with MDR TB case count relative to total TB case count. Our findings might inform spatially targeted TB control strategies and provide insights for generating hypotheses about the nature of the relationship between DS and MDR TB in Ho Chi Minh City and the wider southeastern region of Asia.

Published
2024
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34. Single-cell analysis of memory B cells from top neutralizers reveals multiple sites of vulnerability within HCMV Trimer and Pentamer.

Author

Zehner M, Alt M, Ashurov A, Goldsmith JA, Spies R, Weiler N, Lerma J, Gieselmann L, Stöhr D, Gruell H, Schultz EP, Kreer C, Schlachter L, Janicki H, Laib Sampaio K, Stegmann C, Nemetchek MD, Dähling S, Ullrich L, Dittmer U, Witzke O, Koch M, Ryckman BJ, Lotfi R, McLellan JS, Krawczyk A, Sinzger C, and Klein F

Subjects
Infant, Newborn, Humans, Membrane Glycoproteins, Antibodies, Neutralizing, Memory B Cells, Antibodies, Viral, Single-Cell Analysis, Cytomegalovirus, Viral Envelope Proteins
Abstract

Human cytomegalovirus (HCMV) can cause severe diseases in fetuses, newborns, and immunocompromised individuals. Currently, no vaccines are approved, and treatment options are limited. Here, we analyzed the human B cell response of four HCMV top neutralizers from a cohort of 9,000 individuals. By single-cell analyses of memory B cells targeting the pentameric and trimeric HCMV surface complexes, we identified vulnerable sites on the shared gH/gL subunits as well as complex-specific subunits UL 128/130/131A and gO. Using high-resolution cryogenic electron microscopy, we revealed the structural basis of the neutralization mechanisms of antibodies targeting various binding sites. Moreover, we identified highly potent antibodies that neutralized a broad spectrum of HCMV strains, including primary clinical isolates, that outperform known antibodies used in clinical trials. Our study provides a deep understanding of the mechanisms of HCMV neutralization and identifies promising antibody candidates to prevent and treat HCMV infection., Competing Interests: Declaration of interests A patent application encompassing aspects of this work has been filed by the University of Cologne, the University of Ulm, and the University of Duisburg-Essen, listing F.K., C. Sinzger, A.K., M.Z., and M.A. as inventors., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Published
2023
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35. Sputum Color as a Marker for Bacteria in Acute Exacerbations of Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-analysis.

Author

Spies R, Potter M, Hollamby R, van der Walt S, Hohlfeld A, Ochodo E, and Van Zyl-Smit R

Subjects
Humans, Cross-Sectional Studies, Prospective Studies, Cough, Bacteria, Disease Progression, Sputum, Pulmonary Disease, Chronic Obstructive
Abstract

Rationale: Diagnosing bacterial infection as the etiology in acute exacerbations of chronic obstructive pulmonary disease (AECOPDs) remains challenging. Sputum discoloration is easily measured and often used as a marker of bacterial infection in AECOPD, although high-quality evidence for this practice is lacking. Objectives: To determine the diagnostic accuracy of sputum color as a marker for bacteria in AECOPD. Methods: Articles were searched for in electronic databases, and the gray literature were reviewed. Quality assessment of included articles was performed using the revised Quality Assessment of Diagnostic Accuracy Studies tool. A meta-analysis was conducted using a bivariate logistic regression model with random effects. Analysis was conducted on individual sputum samples rather than on individual participants so that each sample represented a unique index test. Results: Of the 1,600 candidate studies, 13 eligible studies satisfied the inclusion criteria. These included prospective cohort studies ( n  = 3), cross-sectional studies ( n  = 3), and secondary analyses of randomized controlled trials ( n  = 7). The included studies were all from Europe and North America. Most studies scored high risk of bias in at least one domain. In total, this systematic review and meta-analysis included 5,770 sputum samples. The estimated pooled sensitivity and specificity were 81% (95% confidence interval [CI], 70-88%) and 50% (95% CI, 35-65%), respectively, and these results were not significantly altered in a series of sensitivity analyses. Conclusions: Sputum color has limited value as a stand-alone test in diagnosing bacterial infection as the etiology in AECOPD because of its moderate sensitivity and poor specificity.

Published
2023
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36. The Evolving Spectrum of Kidney Histology in HIV-Positive Patients in South Africa.

Author

Wearne N, Manning K, Price B, Rayner BL, Davidson B, Jones ES, Spies R, Cunningham C, Omar A, Ash S, Bohmer R, Kennedy L, and Post F

Abstract

Introduction: Sub-Saharan Africa remains challenged by the highest burden of human immunodeficiency virus (HIV), an epidemic of tuberculosis (TB), and increasing number of people with HIV (PWH) on antiretroviral therapy (ART), all of which may result in kidney injury., Methods: This observational cohort study describes the spectrum of kidney disease in PWH in South Africa, between 2005 and 2020. Kidney biopsies were analyzed in 4 time periods as follows: early ART rollout (2005-2009), tenofovir disoproxil (TDF) introduction (2010-2012), TDF-based fixed dose combination (2013-2015), and ART at HIV diagnosis (2016-2020). Logistic regression was used to identify factors associated with HIV-associated nephropathy or focal segmental glomerulosclerosis (HIVAN/FSGS) and tubulointerstitial disease (TID)., Results: We included 671 participants (median age 36, interquartile range, 21-44 years; 49% female; median CD4 cell count 162 [interquartile range, 63-345] cells/mm 3 ). Over time, ART (31%-65%, P  < 0.001), rate of HIV suppression (20%-43%, P  < 0.001), nonelective biopsies (53%-72%, P  < 0.001), and creatinine at biopsy (242-449 μmol/l, P  < 0.001) increased. A decrease in HIVAN (45%-29% P  < 0.001) was accompanied by an increase in TID (13%-33%, P  < 0.001). Granulomatous interstitial nephritis accounted for 48% of TID, mostly because of TB. Exposure to TDF was strongly associated with TID (adjusted odds ratio 2.99, 95% confidence interval 1.89-4.73 P  < 0.001)., Conclusion: As ART programs intensified and increasingly used TDF, the spectrum of kidney histology in PWH evolved from a predominance of HIVAN in the early ART era to TID in recent times. The increase in TID is likely due to multiple exposures that include TB, sepsis, and TDF as well as other insults., (© 2023 Published by Elsevier Inc. on behalf of the International Society of Nephrology.)

Published
2023
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37. Multisystem cytomegalovirus end-organ disease in a patient with advanced HIV.

Author

Spies R, Joubert P, Chetty D, Dlamini S, and Moosa MS

Abstract

Cytomegalovirus (CMV) infection is common in people living with HIV, but multisystem CMV end-organ disease (EOD) is rare following the introduction of effective antiretroviral therapy. We present the case of a patient with advanced HIV and multisystem manifestations of CMV EOD., Contributions: This case report highlights the potential morbidity and mortality associated with CMV disease in patients with advanced HIV. Clinicians should be vigilant in considering CMV EOD in patients with advanced HIV and visual, neurological and gastointestinal symptoms., Competing Interests: The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article., (© 2022. The Authors.)

Published
2022
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38. Rifampicin resistance and mortality in patients hospitalised with HIV-associated tuberculosis.

Author

Spies R, Schutz C, Ward A, Balfour A, Shey M, Nicol M, Burton R, Sossen B, Wilkinson R, Barr D, and Meintjes G

Abstract

Background: Patients with HIV and drug-resistant tuberculosis (TB) are at high risk of death., Objectives: We investigated the association between rifampicin-resistant TB (RR-TB) and mortality in a cohort of patients who were admitted to hospital at the time of TB diagnosis., Method: Adults hospitalised at Khayelitsha Hospital and diagnosed with HIV-associated TB during admission, were enrolled between 2013 and 2016. Clinical, biochemical and microbiological data were prospectively collected and participants were followed up for 12 weeks., Results: Participants with microbiologically confirmed TB ( n = 482) were enrolled a median of two days (interquartile range [IQR]: 1-3 days) following admission. Fifty-three participants (11.0%) had RR-TB. Participants with rifampicin-susceptible TB (RS-TB) received appropriate treatment a median of one day (IQR: 1-2 days) following enrolment compared to three days (IQR: 1-9 days) in participants with RR-TB. Eight participants with RS-TB (1.9%) and six participants with RR-TB (11.3%) died prior to the initiation of appropriate treatment. Mortality at 12 weeks was 87/429 (20.3%) in the RS-TB group and 21/53 (39.6%) in the RR-TB group. RR-TB was a significant predictor of 12-week mortality (hazard ratio: 1.88; 95% confidence interval: 1.07-3.29; P = 0.03)., Conclusion: Mortality at 12 weeks in participants with RR-TB was high compared to participants with RS-TB. Delays in the initiation of appropriate treatment and poorer regimen efficacy are proposed as contributors to higher mortality in hospitalised patients with HIV and RR-TB., Competing Interests: The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article., (© 2022. The Authors.)

Published
2022
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39. Children in foster care with symptoms of reactive attachment disorder: feasibility randomised controlled trial of a modified video-feedback parenting intervention.

Author

Oliveira P, Barge L, Stevens E, Byford S, Shearer J, Spies R, Comyn J, Langley K, Ramchandani P, Wright B, Woolgar M, Kennedy E, Scott S, Barlow J, Glaser D, Senior R, Fonagy P, and Fearon P

Abstract

Background: Looked-after children are at risk of suboptimal attachment patterns and reactive attachment disorder (RAD). However, access to interventions varies widely, and there are no evidence-based interventions for RAD., Aims: To modify an existing parenting intervention for children with RAD in the UK foster care setting, and test the feasibility of conducting a randomised controlled trial (RCT) of the modified intervention., Method: The intervention was modified with expert input and tested on a case series. A feasibility and pilot RCT compared the new intervention with usual care. Foster carers and children in their care aged ≤6 years were recruited across nine local authorities, with 1:1 allocation and blind post-treatment assessments. The modified intervention was delivered in-home by trained mental health professionals over 4-6 months. Children were assessed for RAD symptoms, attachment quality and emotional/behavioural difficulties, and foster carers were assessed for sensitivity and stress., Results: Minimal changes to the intervention programme were necessary, and focused on improving its suitability for the UK foster care context. Recruitment was challenging, and remained below target despite modifications to the protocol and the inclusion of additional sites. Thirty families were recruited to the RCT; 15 were allocated to each group. Most other feasibility outcomes were favourable, particularly high numbers of data and treatment completeness. The revised intervention was positively received by practitioners and foster carers., Conclusions: A large-scale trial may be feasible, but only if recruitment barriers can be overcome. Dedicated resources to support recruitment within local authorities and wider inclusion criteria are recommended.

Published
2022
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40. Co-producing to understand what matters to young people living in youth residential rehabilitation services.

Author

Ennals P, Lessing K, Spies R, Egan R, Hemus P, Droppert K, Tidhar M, Wood T, van Dijk C, Bride R, Asche A, Bendall S, and Simmons M

Subjects
Adolescent, Grounded Theory, Humans, Mental Health
Abstract

Aim: Residential group care is an important service for vulnerable young people experiencing mental health, substance abuse and/or behavioural challenges. Yet little is written about specific models and their outcomes, especially from the perspectives of the young people who use these services. This project aimed to explore what matters to young people living in a 12-month voluntary residential program for young people aged 16-25., Methods: This participatory action research study was co-produced with Youth Residential Rehabilitation Service residents and staff as co-researchers. A steering group comprising residents, staff and researchers oversaw all research stages. 18 young people and 17 staff members participated in either individual or group interviews to discuss what was important in Youth Residential Rehabilitation Services. Data analysis drew on grounded theory techniques; subsequent codes and themes were refined in the steering group., Results: We identified the 'change work' that young people were expected to do, and the milieu factors that created a supportive environment. As young people were figuring out their directions and learning new skills, they needed to be understood as the developing expert of their own lives. Real relationships with staff and other young people created a culture of belonging, safety and feeling known. These findings are metaphorically captured in the image of an egg., Conclusions: Our study highlights that real relationships between all Youth Residential Rehabilitation Service community members are central to creating the atmosphere of safety and belonging that enables healing and self-development to occur., (© 2021 John Wiley & Sons Australia, Ltd.)

Published
2022
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41. Extreme Learning Machine Design for Dealing with Unrepresentative Features.

Author

Nieto N, Ibarrola FJ, Peterson V, Rufiner HL, and Spies R

Subjects
Algorithms, Electroencephalography, Research Design, Brain-Computer Interfaces
Abstract

Extreme Learning Machines (ELMs) have become a popular tool for the classification of electroencephalography (EEG) signals for Brain Computer Interfaces. This is so mainly due to their very high training speed and generalization capabilities. Another important advantage is that they have only one hyperparameter that must be calibrated: the number of hidden nodes. While most traditional approaches dictate that this parameter should be chosen smaller than the number of available training examples, in this article we argue that, in the case of problems in which the data contain unrepresentative features, such as in EEG classification problems, it is beneficial to choose a much larger number of hidden nodes. We characterize this phenomenon, explain why this happens and exhibit several concrete examples to illustrate how ELMs behave. Furthermore, as searching for the optimal number of hidden nodes could be time consuming in enlarged ELMs, we propose a new training scheme, including a novel pruning method. This scheme provides an efficient way of finding the optimal number of nodes, making ELMs more suitable for dealing with real time EEG classification problems. Experimental results using synthetic data and real EEG data show a major improvement in the training time with respect to most traditional and state of the art ELM approaches, without jeopardising classification performance and resulting in more compact networks., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Published
2022
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42. A motor imagery vs. rest dataset with low-cost consumer grade EEG hardware.

Author

Peterson V, Galván C, Hernández H, Saavedra MP, and Spies R

Abstract

The data consist of electroencephalography (EEG) signals acquired by means of low-cost consumer-grade devices from 10 participants (four females, right-handed, mean age ± SD = 26.1 ± 4.0 years) without any previous experience in Brain-Computer Interfaces (BCIs) usage. The BCI protocol consisted of two conditions, namely the kinesthetic imagination of grasping movement (motor imagery, MI) of the dominant hand and a rest/idle condition. Five protocol runs were required to be performed by each participant in a single-day session, of about 1.5 h. The first run, called RUN0, involved 5 trials of real grasping movement together with the same number of trials in a rest condition. This first run was done to both better explain the protocol and to encourage the participant to focus on the sensation of executing the movement. The rest of the runs (RUN1-RUN4) were identical, consisting of 20 trials for each condition presented in a random order. The electrical brain activity was registered from 15 electrodes covering the sensorimotor area, at a sampling frequency of 125 Hz. Muscle activity of the dominant hand was controlled via the electromyography (EMG) activity by two electrodes placed at two antagonist muscles involved in the flexion/extension of the wrist. The recordings were performed in a non-shielded office, by means of low-cost consumer grade devices and free multi-platform open source software. The EMG corruption level was analyzed and EEG trials for which the EMG activity was higher than a prescribed threshold value, were discarded. During acquisition, EEG data was digitally band-pass filtered between 0.5 and 45 Hz. These data provide a motor imagery vs. rest EEG dataset, relevant for BCI for motor rehabilitation applications. Since the recordings were performed by means of low-cost consumer grade devices in a non-controlled environment, this dataset provides an excellent source for exploring robust brain decoding techniques for future in-home BCI usage., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2022 The Author(s).)

Published
2022
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43. Introducing the youth residential rehabilitation service: An operational and experiential overview of a psychosocial residential support option for young people experiencing mental health challenges.

Author

Spies R, Ennals P, Egan R, Hemus P, Gonzales R, Droppert K, Tidhar M, McMullan S, Lessing K, Wood T, Bride R, Bendall S, and Simmons M

Subjects
Adolescent, Adult, Australia, Hope, Humans, Young Adult, Mental Health, Psychosocial Support Systems
Abstract

Aim: A range of residential supports is available for young people experiencing mental health challenges. One Australian example is the Youth Residential Rehabilitation Service, which provides up to 12 months of intensive psychosocial support in a residential setting to young people aged 16-25 experiencing serious mental health challenges. This paper aimed to add to the scant literature on these services, describing the experiences of young people and staff members across the duration of a stay., Methods: This study drew on collaborative autoethnography to engage and centre the direct lived experience of young people who had lived, and staff who had worked, in a Youth Residential Rehabilitation Service., Results: We identified three phases that young people typically journey through during their stay at the service. The Arriving phase was marked by appropriate referrals, a warm welcome, a period of settling in and the development of trusting relationships. The Discovering phase saw young people identifying and enacting their strengths, hopes and values. Community connections were a focus of the Continuing phase as lives after service exit were envisioned and created., Conclusions: Drawing on collaborative autoethnography methods represents one approach to amplify the voice of young people in service design and evaluation. This paper richly described some of the possibilities and complexities of the Youth Residential Rehabilitation Service experience, which can be used to inform the service's pacing and structure of support., (© 2021 John Wiley & Sons Australia, Ltd.)

Published
2022
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44. SARS-CoV-2 infection in public hospital medical doctors in an Eastern Cape metro.

Author

Spies R, Potter M, Govender S, Kirk L, Rauch S, and Black J

Abstract

Background: Evidence-based Infection Prevention and Control (IPC) measures are critical in protecting medical doctors from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Concerns surrounding access to personal protective equipment (PPE), compliance with IPC measures and the quality of available PPE have been raised as possible causes for high rates of SARS-CoV-2 infection in medical doctors in high transmission settings. This study aimed to determine the prevalence of SARS-CoV-2 infection and the risk factors for occupational infection in doctors in the hospitals in Nelson Mandela Bay (NMB)., Methods: We conducted a cross-sectional study wherein we electronically surveyed medical doctors in public-sector NMB hospitals from 01 March 2020 to 31 December 2020. We collected demographic, health, occupational and SARS-CoV-2 infection and exposure data. Categorical data were described as proportions and a multiple variable logistic regression model was used to identify risk factors for SARS-CoV-2 infection., Results: The survey was distributed amongst 498 doctors, 141 (28%) of whom replied. Forty-three (31%) participants reported that they had tested positive for SARS-CoV-2 during the study period. Eighty-nine participants (64%) reported inadequate access to PPE whilst only 68 (49%) participants adhered to PPE recommendations when interacting with patients with confirmed or suspected SARS-CoV-2 infection. We were unable to identify any significant predictors of SARS-CoV-2 infection., Conclusion: This study demonstrates a high prevalence of SARS-CoV-2 infection in public hospital doctors in NMB. Most participants reported inadequate access to PPE and poor compliance with IPC protocols. These findings suggest an urgent need for the improved implementation of IPC measures to protect doctors from SARS-CoV-2 infection., Competing Interests: The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article., (© 2022. The Authors.)

Published
2022
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45. Thinking out loud, an open-access EEG-based BCI dataset for inner speech recognition.

Author

Nieto N, Peterson V, Rufiner HL, Kamienkowski JE, and Spies R

Subjects
Artificial Intelligence, Brain, Electroencephalography, Humans, Brain-Computer Interfaces, Speech Perception
Abstract

Surface electroencephalography is a standard and noninvasive way to measure electrical brain activity. Recent advances in artificial intelligence led to significant improvements in the automatic detection of brain patterns, allowing increasingly faster, more reliable and accessible Brain-Computer Interfaces. Different paradigms have been used to enable the human-machine interaction and the last few years have broad a mark increase in the interest for interpreting and characterizing the "inner voice" phenomenon. This paradigm, called inner speech, raises the possibility of executing an order just by thinking about it, allowing a "natural" way of controlling external devices. Unfortunately, the lack of publicly available electroencephalography datasets, restricts the development of new techniques for inner speech recognition. A ten-participant dataset acquired under this and two others related paradigms, recorded with an acquisition system of 136 channels, is presented. The main purpose of this work is to provide the scientific community with an open-access multiclass electroencephalography database of inner speech commands that could be used for better understanding of the related brain mechanisms., (© 2022. The Author(s).)

Published
2022
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46. Deep Exclusive Electroproduction of π^{0} at High Q^{2} in the Quark Valence Regime.

Author

Dlamini M, Karki B, Ali SF, Lin PJ, Georges F, Ko HS, Israel N, Rashad MNH, Stefanko A, Adikaram D, Ahmed Z, Albataineh H, Aljawrneh B, Allada K, Allison S, Alsalmi S, Androic D, Aniol K, Annand J, Atac H, Averett T, Ayerbe Gayoso C, Bai X, Bane J, Barcus S, Bartlett K, Bellini V, Beminiwattha R, Bericic J, Biswas D, Brash E, Bulumulla D, Campbell J, Camsonne A, Carmignotto M, Castellano J, Chen C, Chen JP, Chetry T, Christy ME, Cisbani E, Clary B, Cohen E, Compton N, Cornejo JC, Covrig Dusa S, Crowe B, Danagoulian S, Danley T, De Persio F, Deconinck W, Defurne M, Desnault C, Di D, Duer M, Duran B, Ent R, Fanelli C, Franklin G, Fuchey E, Gal C, Gaskell D, Gautam T, Glamazdin O, Gnanvo K, Gray VM, Gu C, Hague T, Hamad G, Hamilton D, Hamilton K, Hansen O, Hauenstein F, Henry W, Higinbotham DW, Holmstrom T, Horn T, Huang Y, Huber GM, Hyde C, Ibrahim H, Jen CM, Jin K, Jones M, Kabir A, Keppel C, Khachatryan V, King PM, Li S, Li W, Liu J, Liu H, Liyanage A, Magee J, Malace S, Mammei J, Markowitz P, McClellan E, Meddi F, Meekins D, Mesik K, Michaels R, Mkrtchyan A, Montgomery R, Muñoz Camacho C, Myers LS, Nadel-Turonski P, Nazeer SJ, Nelyubin V, Nguyen D, Nuruzzaman N, Nycz M, Obretch OF, Ou L, Palatchi C, Pandey B, Park S, Park K, Peng C, Pomatsalyuk R, Pooser E, Puckett AJR, Punjabi V, Quinn B, Rahman S, Reimer PE, Roche J, Sapkota I, Sarty A, Sawatzky B, Saylor NH, Schmookler B, Shabestari MH, Shahinyan A, Sirca S, Smith GR, Sooriyaarachchilage S, Sparveris N, Spies R, Su T, Subedi A, Sulkosky V, Sun A, Thorne L, Tian Y, Ton N, Tortorici F, Trotta R, Urciuoli GM, Voutier E, Waidyawansa B, Wang Y, Wojtsekhowski B, Wood S, Yan X, Ye L, Ye Z, Yero C, Zhang J, Zhao Y, and Zhu P

Abstract

We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of x&#95;{B} (0.36, 0.48, and 0.60) and Q^{2} (3.1 to 8.4  GeV^{2}) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσ&#95;{T}/dt+εdσ&#95;{L}/dt, dσ&#95;{TT}/dt, dσ&#95;{LT}/dt, and dσ&#95;{LT^{'}}/dt are extracted as a function of the proton momentum transfer t-t&#95;{min}. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.

Published
2021
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47. Sputum colour as a marker for bacteria in acute exacerbations of COPD: protocol for a systematic review and meta-analysis.

Author

Spies R, Potter M, Hollamby R, van der Walt S, Hohlfeld A, Ochodo E, and van Zyl-Smit RN

Subjects
Bacteria, Color, Humans, Meta-Analysis as Topic, Sputum, Systematic Reviews as Topic, Pulmonary Disease, Chronic Obstructive diagnosis, Quality of Life
Abstract

Background: Chronic obstructive pulmonary disease (COPD) is a major cause of years of life lost globally. Acute exacerbations of COPD (AECOPD) drive disease progression, reduce quality of life and are a source of mortality in COPD. Approximately 50% of AECOPD are due to bacterial infections. Diagnosing bacterial infection as the aetiology of AECOPD however remains challenging as investigations are limited by practicality, accuracy and expense. Clinicians have traditionally used sputum colour as a marker of bacterial infection in AECOPD, despite the lack of high-quality evidence for this practice. The aim of this systematic review and meta-analysis is to determine the diagnostic accuracy of sputum colour in the diagnosis of bacterial causes of AECOPD., Methods: Articles will be searched for in electronic databases (MEDLINE, Google Scholar Scopus, Web of Science, Africa-Wide, CINAHL and Health Source Nursing Academy) and we will conduct a review of citation indexes and the grey literature. Two reviewers will independently conduct study selection, against pre-defined eligibility criteria, data extraction and quality assessment of included articles using the QUADAS-2 tool. We will perform a meta-analysis using a bivariate logistic regression model with random effects. We will explore heterogeneity through the visual examination of the forest plots of sensitivities and specificities and through the inclusion of possible sources of heterogeneity as covariates in a meta-regression model if sufficient studies are included in the analysis. We also perform a sensitivity analysis to explore the effect of study quality on our findings. The results of this review will be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement and will be submitted for peer-review and publication., Discussion: The findings of this review will assist clinicians in diagnosing the aetiology of AECOPD and may have important implications for decision making in resource-limited settings, as well as for antimicrobial stewardship., Systematic Review Registration: PROSPERO CRD42019141498., (© 2021. The Author(s).)

Published
2021
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48. Concept and development of an interactive tool for trial recruitment planning and management.

Author

Spies R, Siegfried N, Myers B, and Grobbelaar SS

Subjects
Humans, South Africa, Budgets, Research Personnel
Abstract

Background: Predicting and monitoring recruitment in large, complex trials is essential to ensure appropriate resource management and budgeting. In a novel partnership between clinical trial investigators of the South African Medical Research Council and industrial engineers from the Stellenbosch University Health Systems Engineering and Innovation Hub, we developed a trial recruitment tool (TRT). The objective of the tool is to serve as a computerised decisions-support system to aid the planning and management phases of the trial recruitment process., Method: The specific requirements of the TRT were determined in several workshops between the partners. A Poisson process simulation model was formulated and incorporated in the TRT to predict the recruitment duration. The assumptions underlying the model were made in consultation with the trial team at the start of the project and were deemed reasonable. Real-world data extracted from a current cluster trial, Project MIND, based in 24 sites in South Africa was used to verify the simulation model and to develop the monitoring component of the TRT., Results: The TRT comprises a planning and monitoring component. The planning component generates different trial scenarios for predicted trial recruitment duration based on user inputs, e.g. number of sites, initiation delays. The monitoring component uses and analyses the data retrieved from the trial management information system to generate different levels of information, displayed visually on an interactive, user-friendly dashboard. Users can analyse the results at trial or site level, changing input parameters to see the resultant effect on the duration of trial recruitment., Conclusion: This TRT is an easy-to-use tool that assists in the management of the trial recruitment process. The TRT has potential to expedite improved management of clinical trials by providing the appropriate information needed for the planning and monitoring of the trial recruitment phase. This TRT extends prior tools describing historic recruitment only to using historic data to predict future recruitment. The broader project demonstrates the value of collaboration between clinicians and engineers to optimise their respective skillsets.

Published
2021
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49. Predictors and Prognosis of HIV-Associated Nephropathy on Kidney Biopsy in South Africa.

Author

Bookholane H, Wearne N, Surapaneni A, Ash S, Berghammer-Böhmer R, Omar A, Spies R, and Grams ME

Abstract

Introduction: South Africa has the highest prevalence of HIV in the world. The epidemiology of kidney disease among people with HIV infections is well-described in the United States. However, there are limited data coming from South Africa, particularly that involve kidney biopsies. The purpose of this study was to determine what, if any, patient factors are predictive of HIV-associated nephropathy (HIVAN) on kidney biopsy in a South African kidney biopsy cohort., Methods: This study prospectively collected data of all patients infected with HIV referred to the Groote Schuur Hospital (GSH) renal unit for a kidney biopsy from 2002 to 2018., Results: There were 419 patients included in the study. Mean age was 36.5 years (SD, 9.4); 219 (52.3%) were women; and all were black. Seventy-nine patients (18.9%) were on dialysis at the time of biopsy; the mean estimated glomerular filtration rate among the remainder was 41.4 ml/min per 1.73 m 2 (SD, 39.2). Only 163 patients (47.1%) were known to be taking antiretroviral therapy (ART) at the time of biopsy. There were 246 (58.7%) cases of HIVAN detected, and they were comparable on age, sex, kidney function, and kidney size to those with kidney disease of other causes but were less likely to be taking ART ( P < 0.001). Biopsy confirmed HIVAN was associated with mortality (adjusted hazard ratio, 1.77; 95% confidence interval [CI]: 1.07-2.91; P = 0.025), and the use of ART at biopsy was protective (adjusted hazard ratio, 0.52; 95% CI, 0.32-0.84, P = 0.008). The proportion of HIVAN on biopsy decreased and the proportion taking ART increased from 2002 to 2018 ( P for trend for both < 0.001)., Conclusion: In summary, HIVAN was the most common etiology of kidney disease in this biopsy cohort from South Africa; however, the proportion with biopsy-proven HIVAN declined over time, perhaps in the setting of greater ART availability., (© 2020 International Society of Nephrology. Published by Elsevier Inc.)

Published
2020
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