146 results on '"Wikus, P."'
Search Results
2. Examining intergenerational risk factors for conduct problems using polygenic scores in the Norwegian Mother, Father and Child Cohort Study
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Frach, Leonard, Barkhuizen, Wikus, Allegrini, Andrea G., Ask, Helga, Hannigan, Laurie J., Corfield, Elizabeth C., Andreassen, Ole A., Dudbridge, Frank, Ystrom, Eivind, Havdahl, Alexandra, and Pingault, Jean-Baptiste
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- 2024
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3. Author Correction: Africa needs context-relevant evidence to shape its clean energy future
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Mulugetta, Yacob, Sokona, Youba, Trotter, Philipp A., Fankhauser, Samuel, Omukuti, Jessica, Somavilla Croxatto, Lucas, Steffen, Bjarne, Tesfamichael, Meron, Abraham, Edo, Adam, Jean-Paul, Agbemabiese, Lawrence, Agutu, Churchill, Aklilu, Mekalia Paulos, Alao, Olakunle, Batidzirai, Bothwell, Bekele, Getachew, Dagnachew, Anteneh G., Davidson, Ogunlade, Denton, Fatima, Diemuodeke, E. Ogheneruona, Egli, Florian, Eshetu, Gebrekidan Gebresilassie, Gebreslassie, Mulualem, Goundiam, Mamadou, Gujba, Haruna Kachalla, Hailu, Yohannes, Hawkes, Adam D., Hirmer, Stephanie, Hoka, Helen, Howells, Mark, Isah, Abdulrasheed, Kammen, Daniel, Kemausuor, Francis, Khennas, Ismail, Kruger, Wikus, Malo, Ifeoma, Mofor, Linus, Nago, Minette, Nock, Destenie, Okereke, Chukwumerije, Ouedraogo, S. Nadia, Probst, Benedict, Schmidt, Maria, Schmidt, Tobias S., Shenga, Carlos, Sokona, Mohamed, Steckel, Jan Christoph, Sterl, Sebastian, Tembo, Bernard, Tomei, Julia, Twesigye, Peter, Watson, Jim, Winkler, Harald, and Yussuff, Abdulmutalib
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- 2024
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4. First Flight Performance of the Micro-X Microcalorimeter X-Ray Sounding Rocket
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Adams, Joseph S., Baker, Robert, Bandler, Simon R., Bastidon, Noemie, Castro, Daniel, Danowksi, Meredith E., Doriese, William B., Eckart, Megan E., Figueroa-Feliciano, Enectali, Fuhrman, Joshua, Goldfinger, David C., Heine, Sarah N. T., Hilton, Gene, Hubbard, Antonia J. F., Jardin, Daniel, Kelley, Richard L., Kilbourne, Caroline A., Leman, Steven W., Manzagol-Harwood, Renee E., McCammon, Dan, Oakley, Philip H. H., Okajima, Takashi, Porter, Frederick Scott, Reintsema, Carl D., Rutherford, John, Saab, Tarek, Sato, Kosuke, Serlemitsos, Peter, Smith, Stephen J., Soong, Yang, and Wikus, Patrick
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Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
The flight of the Micro-X sounding rocket on July 22, 2018 marked the first operation of Transition-Edge Sensors and their SQUID readouts in space. The instrument combines the microcalorimeter array with an imaging mirror to take high-resolution spectra from extended X-ray sources. The first flight target was the Cassiopeia~A Supernova Remnant. While a rocket pointing malfunction led to no time on-target, data from the flight was used to evaluate the performance of the instrument and demonstrate the flight viability of the payload. The instrument successfully achieved a stable cryogenic environment, executed all flight operations, and observed X-rays from the on-board calibration source. The flight environment did not significantly affect the performance of the detectors compared to ground operation. The flight provided an invaluable test of the impact of external magnetic fields and the instrument configuration on detector performance. This flight provides a milestone in the flight readiness of these detector and readout technologies, both of which have been selected for future X-ray observatories.
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- 2022
5. Clinical Coxiella burnetii infection in sable and roan antelope in South Africa
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Wikus Wiedeman, Akorfa B. Glover, Johan Steyl, Jacques O'Dell, and Henriette van Heerden
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coxiella burnetii ,sable ,roan ,abortion ,south africa ,Veterinary medicine ,SF600-1100 - Abstract
Various zoonotic microorganisms cause reproductive problems such as abortions and stillbirths, leading to economic losses on farms, particularly within livestock. In South Africa, bovine brucellosis is endemic in cattle, and from 2013–2018, outbreaks of Brucella melitensis occurred in sable. Coxiella burnetii, the agent responsible for the zoonotic disease known as Q-fever and/or coxiellosis, also causes reproductive problems and infects multiple domestic animal species worldwide, including humans. However, little is known of this disease in wildlife. With the expansion of the wildlife industry in South Africa, diseases like brucellosis and coxiellosis can significantly impact herd breeding success because of challenges in identifying, managing and treating diseases in wildlife populations. This study investigated samples obtained from aborted sable and roan antelope, initially suspected to be brucellosis, from game farms in South Africa using serology tests and ruminant VetMAX™ polymerase chain reaction (PCR) abortion kit. The presence of C. burnetii was confirmed with PCR in a sable abortion case, while samples from both sable and roan were seropositive for C. burnetii indirect enzyme-linked immunosorbent assay (iELISA). This study represents the initial report of C. burnetii infection in sable and roan antelope in South Africa. Epidemiological investigations are crucial to assess the risk of C. burnetii in sable and roan populations, as well as wildlife and livestock in general, across South Africa. This is important in intensive farming practices, particularly as Q-fever, being a zoonotic disease, poses a particular threat to the health of veterinarians and farm workers as well as domestic animals. Contribution: A report of clinical C. burnetii infection in the wildlife industry contributes towards the limited knowledge of this zoonotic disease in South Africa.
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- 2024
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6. Genetic nurture versus genetic transmission of risk for ADHD traits in the Norwegian Mother, Father and Child Cohort Study
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Pingault, Jean-Baptiste, Barkhuizen, Wikus, Wang, Biyao, Hannigan, Laurie J., Eilertsen, Espen Moen, Corfield, Elizabeth, Andreassen, Ole A., Ask, Helga, Tesli, Martin, Askeland, Ragna Bugge, Davey Smith, George, Stoltenberg, Camilla, Davies, Neil M., Reichborn-Kjennerud, Ted, Ystrom, Eivind, and Havdahl, Alexandra
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- 2023
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7. First operation of Transition-Edge Sensors in space with the Micro-X sounding rocket
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Adams, J. S., Baker, R., Bandler, S. R., Bastidon, N., Danowski, M. E., Doriese, W. B., Eckart, M. E., Figueroa-Feliciano, E., Fuhrman, J., Goldfinger, D. C., Heine, S. N. T., Hilton, G. C., Hubbard, A. J. F., Jardin, D., Kelley, R. L., Kilbourne, C. A., Manzagol-Harwood, R. E., McCammon, D., Okajima, T., Porter, F. S., Reintsema, C. D., Serlemitsos, P., Smith, S. J., and Wikus, P.
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Astrophysics - Instrumentation and Methods for Astrophysics ,High Energy Physics - Experiment ,Physics - Instrumentation and Detectors - Abstract
With its first flight in 2018, Micro-X became the first program to fly Transition-Edge Sensors and their SQUID readouts in space. The science goal was a high-resolution, spatially resolved X-ray spectrum of the Cassiopeia A Supernova Remnant. While a rocket pointing error led to no time on target, the data was used to demonstrate the flight performance of the instrument. The detectors observed X-rays from the on-board calibration source, but a susceptibility to external magnetic fields limited their livetime. Accounting for this, no change was observed in detector response between ground operation and flight operation. This paper provides an overview of the first flight performance and focuses on the upgrades made in preparation for reflight. The largest changes have been upgrading the SQUIDs to mitigate magnetic susceptibility, synchronizing the clocks on the digital electronics to minimize beat frequencies, and replacing the mounts between the cryostat and the rocket skin to improve mechanical integrity. As the first flight performance was consistent with performance on the ground, reaching the instrument goals in the laboratory is considered a strong predictor of future flight performance.
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- 2021
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8. A genetically informed Registered Report on adverse childhood experiences and mental health
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Baldwin, Jessie R., Sallis, Hannah M., Schoeler, Tabea, Taylor, Mark J., Kwong, Alex S. F., Tielbeek, Jorim J., Barkhuizen, Wikus, Warrier, Varun, Howe, Laura D., Danese, Andrea, McCrory, Eamon, Rijsdijk, Fruhling, Larsson, Henrik, Lundström, Sebastian, Karlsson, Robert, Lichtenstein, Paul, Munafò, Marcus, and Pingault, Jean-Baptiste
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- 2023
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9. Are admission laboratory values in isolation meaningful for predicting surgical outcome in patients with perforated peptic ulcers?
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Wikus W. Mulder, MBChB, MMed (Surg), FCS (SA), Emmanuel Arko-Cobbah, MBChB, MMed (Surg), Cert Trauma Surgery (SA), and Gina Joubert, MSc
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Peptic ulcer ,Perforation ,Emergency surgery ,Mortality ,Laboratory values ,Surgery ,RD1-811 - Abstract
Background: The study aimed to calculate the predictive value of admission laboratory values in patients with perforated peptic ulcers. Methods: A retrospective, cohort analytical, observational study was performed, including patients with surgically confirmed perforated peptic ulcers over a 5-year period. Demographic data and admission laboratory values were collected from hospital electronic databases. Outcomes measured were in-hospital mortality, intensive care unit (ICU) admission and length of stay. The significance of categorical variables was calculated by chi-square and Fisher's exact test. Logistic regression analysis was performed to determine univariately statistically significant variables. Results: In total, 188 patients met the inclusion criteria. The median age was 46 (range 15–87) years with a male predominance of 71.3 % (n = 134). The median length of hospital stay was 7 (range 1–94) days and 31.4 % (n = 59) of patients were admitted to the ICU. Post-operative in-hospital mortality was 25.0 % (n = 47). Predicting the categorical outcome of in-hospital mortality, abnormal haemoglobin, platelet count, urea, creatinine and potassium levels were all found to be statistically significant in the univariate analysis. Age (odds ratio [OR] 1.03), haemoglobin (OR 4.36) and creatinine (OR 7.76) levels were significant in the multivariate analysis. Conclusions: Mortality rate among patients with perforated peptic ulcer disease is still substantial. Admission laboratory values showed statistical significance as outcome indicators and were valuable to assist in predicting the prognosis. An abnormally high serum creatinine level was the strongest single predictor of both mortality and ICU admission. Key message: Initial laboratory findings of patients admitted for perforated peptic ulcer showed that an abnormally high serum creatinine level was the strongest single predictor of both mortality and ICU admission.
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- 2023
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10. Africa needs context-relevant evidence to shape its clean energy future
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Mulugetta, Yacob, Sokona, Youba, Trotter, Philipp A., Fankhauser, Samuel, Omukuti, Jessica, Somavilla Croxatto, Lucas, Steffen, Bjarne, Tesfamichael, Meron, Abraham, Edo, Adam, Jean-Paul, Agbemabiese, Lawrence, Agutu, Churchill, Aklilu, Mekalia Paulos, Alao, Olakunle, Batidzirai, Bothwell, Bekele, Getachew, Dagnachew, Anteneh G., Davidson, Ogunlade, Denton, Fatima, Diemuodeke, E. Ogheneruona, Egli, Florian, Eshetu, Gebrekidan Gebresilassie, Gebreslassie, Mulualem, Goundiam, Mamadou, Gujba, Haruna Kachalla, Hailu, Yohannes, Hawkes, Adam D., Hirmer, Stephanie, Hoka, Helen, Howells, Mark, Isah, Abdulrasheed, Kammen, Daniel, Kemausuor, Francis, Khennas, Ismail, Kruger, Wikus, Malo, Ifeoma, Mofor, Linus, Nago, Minette, Nock, Destenie, Okereke, Chukwumerije, Ouedraogo, S. Nadia, Probst, Benedict, Schmidt, Maria, Schmidt, Tobias S., Shenga, Carlos, Sokona, Mohamed, Steckel, Jan Christoph, Sterl, Sebastian, Tembo, Bernard, Tomei, Julia, Twesigye, Peter, Watson, Jim, Winkler, Harald, and Yussuff, Abdulmutalib
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- 2022
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11. First Operation of TES Microcalorimeters in Space with the Micro-X Sounding Rocket
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Adams, J. S., Baker, R., Bandler, S. R., Bastidon, N., Danowski, M. E., Doriese, W. B., Eckart, M. E., Figueroa-Feliciano, E., Goldfinger, D. C., Heine, S. N. T., Hilton, G. C., Hubbard, A. J. F., Kelley, R. L., Kilbourne, C. A., Manzagol-Harwood, R. E., McCammon, D., Okajima, T., Porter, F. S., Reintsema, C. D., Serlemitsos, P., Smith, S. J., Ullom, J. N., and Wikus, P.
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Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
Micro-X is a sounding rocket-borne instrument that uses a microcalorimeter array to perform high-resolution X-ray spectroscopy. This instrument flew for the first time on July 22nd, 2018 from the White Sands Missile Range, USA. This flight marks the first successful operation of a Transition-Edge Sensor array and its time division multiplexing read-out system in space. This launch was dedicated to the observation of the supernova remnant Cassiopeia A. A failure in the attitude control system prevented the rocket from pointing and led to no time on target. The on-board calibration source provided X-rays in flight, and it is used to compare detector performance during pre-flight integration, flight, and after the successful post-flight recovery. This calibration data demonstrates the capabilities of the detector in a space environment as well as its potential for future flights., Comment: 9 pages, 6 figures, Accepted to the JLTP for LTD-18
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- 2019
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12. Micro-X Sounding Rocket: Transitioning from First Flight to a Dark Matter Configuration
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Adams, J. S., Anderson, A. J., Baker, R., Bandler, S. R., Bastidon, N., Castro, D., Danowski, M. E., Doriese, W. B., Eckart, M. E., Figueroa-Feliciano, E., Goldfinger, D. C., Heine, S. N. T., Hilton, G. C., Hubbard, A. J. F., Kelley, R. L., Kilbourne, C. A., Manzagol-Harwood, R. E., McCammon, D., Okajima, T., Porter, F. S., Reintsema, C. D., Serlemitsos, P., Smith, S. J., and Wikus, P.
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Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,High Energy Physics - Experiment ,Physics - Instrumentation and Detectors - Abstract
The Micro-X sounding rocket flew for the first time on July 22, 2018, becoming the first program to fly Transition-Edge Sensors and multiplexing SQUID readout electronics in space. While a rocket pointing failure led to no time on-target, the success of the flight systems was demonstrated. The successful flight operation of the instrument puts the program in a position to modify the payload for indirect galactic dark matter searches. The payload modifications are motivated by the science requirements of this observation. Micro-X can achieve world-leading sensitivity in the keV regime with a single flight. Dark matter sensitivity projections have been updated to include recent observations and the expected sensitivity of Micro-X to these observed fluxes. If a signal is seen (as seen in the X-ray satellites), Micro-X can differentiate an atomic line from a dark matter signature., Comment: Proceedings of the 18th International Workshop on Low Temperature Detectors (LTD18)
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- 2019
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13. Genetic overlap and causal associations between smoking behaviours and mental health
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Wikus Barkhuizen, Frank Dudbridge, and Angelica Ronald
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Medicine ,Science - Abstract
Abstract Cigarette smoking is a modifiable behaviour associated with mental health. We investigated the degree of genetic overlap between smoking behaviours and psychiatric traits and disorders, and whether genetic associations exist beyond genetic influences shared with confounding variables (cannabis and alcohol use, risk-taking and insomnia). Second, we investigated the presence of causal associations between smoking initiation and psychiatric traits and disorders. We found significant genetic correlations between smoking and psychiatric disorders and adult psychotic experiences. When genetic influences on known covariates were controlled for, genetic associations between most smoking behaviours and schizophrenia and depression endured (but not with bipolar disorder or most psychotic experiences). Mendelian randomization results supported a causal role of smoking initiation on psychiatric disorders and adolescent cognitive and negative psychotic experiences, although not consistently across all sensitivity analyses. In conclusion, smoking and psychiatric disorders share genetic influences that cannot be attributed to covariates such as risk-taking, insomnia or other substance use. As such, there may be some common genetic pathways underlying smoking and psychiatric disorders. In addition, smoking may play a causal role in vulnerability for mental illness.
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- 2021
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14. Vibration Isolation Design for the Micro-X Rocket Payload
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Heine, Sarah N. T., Figueroa-Feliciano, Enectali, Rutherford, John M., Wikus, Patrick, Oakley, Phil, Porter, Frederick S., and McCammon, Dan
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Astrophysics - Instrumentation and Methods for Astrophysics ,Physics - Instrumentation and Detectors - Abstract
Micro-X is a NASA-funded, sounding rocket-borne X-ray imaging spectrometer that will allow high precision measurements of velocity structure, ionization state and elemental composition of extended astrophysical systems. One of the biggest challenges in payload design is to maintain the temperature of the detectors during launch. There are several vibration damping stages to prevent energy transmission from the rocket skin to the detector stage, which causes heating during launch. Each stage should be more rigid than the outer stages to achieve vibrational isolation. We describe a major design effort to tune the resonance frequencies of these vibration isolation stages to reduce heating problems prior to the projected launch in the summer of 2014., Comment: 6 pages, 7 figures, LTD15 Conference Proceedings
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- 2013
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15. Genetic overlap and causal associations between smoking behaviours and mental health
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Barkhuizen, Wikus, Dudbridge, Frank, and Ronald, Angelica
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- 2021
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16. Direct Detection of Antibacterial-Producing Soil Isolates Utilizing a Novel High-Throughput Screening Assay
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Wikus Ernst Laubscher and Marina Rautenbach
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antibiotic discovery ,soil organisms ,bacterial peptide producers ,high throughput assay ,bioluminescence ,Biology (General) ,QH301-705.5 - Abstract
The ever-increasing global threat of common infections developing resistance to current therapeutics is rapidly accelerating the onset of a primitive post-antibiotic era in medicine. The prevention of further antimicrobial resistance development is unlikely due to the continued misuse of antibiotics, augmented by the lack of discovery of novel antibiotics. Screening large libraries of synthetic compounds have yet to offer effective replacements for current antibiotics. Due to historical successes, discovery from large and diverse natural sources and, more specifically, environmental bacteria, may still yield novel alternative antibiotics. However, the process of antibiotic discovery from natural sources is laborious and time-consuming as a result of outdated methodologies. Therefore, we have developed a simple and rapid preliminary screening assay to identify antibacterial-producing bacteria from natural sources. In brief, the assay utilizes the presence or absence of luminescence in bioluminescent reporter bacteria and test bacterium co-cultures in a 96-well plate format to determine the absence or presence of antibacterial compound production. Our assay, called the bioluminescent simultaneous antagonism (BSLA) assay, can accurately distinguish between known antibacterial-producing and non-producing test bacteria. The BSLA assay was validated by screening 264 unknown soil isolates which resulted in the identification of 10 antibacterial-producing isolates, effectively decreasing the pool of isolates for downstream analysis by 96%. By design, the assay is simple and requires only general laboratory equipment; however, we have shown that the assay can be scaled to automated high-throughput screening systems. Taken together, the BSLA assay allows for the rapid pre-screening of unknown bacterial isolates which, when coupled with innovative downstream dereplication and identification technologies, can effectively fast-track antimicrobial discovery.
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- 2022
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17. First Operation of TES Microcalorimeters in Space with the Micro-X Sounding Rocket
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Adams, J. S., Baker, R., Bandler, S. R., Bastidon, N., Danowski, M. E., Doriese, W. B., Eckart, M. E., Figueroa-Feliciano, E., Goldfinger, D. C., Heine, S. N. T., Hilton, G. C., Hubbard, A. J. F., Kelley, R. L., Kilbourne, C. A., Manzagol-Harwood, R. E., McCammon, D., Okajima, T., Porter, F. S., Reintsema, C. D., Serlemitsos, P., Smith, S. J., Ullom, J. N., and Wikus, P.
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- 2020
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18. Micro-X Sounding Rocket: Transitioning from First Flight to a Dark Matter Configuration
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Adams, J. S., Anderson, A. J., Baker, R., Bandler, S. R., Bastidon, N., Castro, D., Danowski, M. E., Doriese, W. B., Eckart, M. E., Figueroa-Feliciano, E., Goldfinger, D. C., Heine, S. N. T., Hilton, G. C., Hubbard, A. J. F., Kelley, R. L., Kilbourne, C. A., Manzagol-Harwood, R. E., McCammon, D., Okajima, T., Porter, F. S., Reintsema, C. D., Serlemitsos, P., Smith, S. J., and Wikus, P.
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- 2020
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19. Genetic and Phenotypic Characteristics of a Multi-strain Probiotic for Broilers
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Neveling, Deon P., Ahire, Jayesh J., Laubscher, Wikus, Rautenbach, Marina, and Dicks, Leon M. T.
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- 2020
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20. Combined Limits on WIMPs from the CDMS and EDELWEISS Experiments
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CDMS, Collaborations, EDELWEISS, Ahmed, Z., Akerib, D. S., Armengaud, E., Arrenberg, S., Augier, C., Bailey, C. N., Balakishiyeva, D., Baudis, L., Bauer, D. A., Benoît, A., Bergé, L., Blümer, J., Brink, P. L., Broniatowski, A., Bruch, T., Brudanin, V., Bunker, R., Cabrera, B., Caldwell, D. O., Censier, B., Chapellier, M., Chardin, G., Charlieux, F., Cooley, J., Coulter, P., Cox, G. A., Cushman, P., Daal, M., Defay, X., De Jesus, M., DeJongh, F., Di Stefano, P. C. F., Dolgorouki, Y., Domange, J., Dumoulin, L., Dragowsky, M. R., Eitel, K., Fallows, S., Figueroa-Feliciano, E., Filippini, J., Filosofov, D., Fourches, N., Fox, J., Fritts, M., Gascon, J., Gerbier, G., Gironnet, J., Golwala, S. R., Gros, M., Hall, J., Hennings-Yeomans, R., Henry, S., Hertel, S. A., Hervé, S., Holmgren, D., Hsu, L., Huber, M. E., Juillard, A., Kamaev, O., Kiveni, M., Kluck, H., Kos, M., Kozlov, V., Kraus, H., Kudryavtsev, V. A., Leman, S. W., Liu, S., Loaiza, P., Mahapatra, R., Mandic, V., Marnieros, S., Martinez, C., McCarthy, K. A., Mirabolfathi, N., Moore, D., Nadeau, P., Navick, X-F., Nelson, H., Nones, C., Ogburn, R. W., Olivieri, E., Pari, P., Pattavina, L., Paul, B., Phipps, A., Pyle, M., Qiu, X., Rau, W., Reisetter, A., Ricci, Y., Robinson, M., Rozov, S., Saab, T., Sadoulet, B., Sander, J., Sanglard, V., Schmidt, B., Schnee, R. W., Scorza, S., Seitz, D. N., Semikh, S., Serfass, B., Sundqvist, K. M., Tarka, M., Torrento-Coello, A. S., Vagneron, L., Verdier, M. -A., Walker, R. J., Wikus, P., Yakushev, E., Yellin, S., Yoo, J., Young, B. A., and Zhang, J.
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Astrophysics - Cosmology and Nongalactic Astrophysics ,High Energy Physics - Experiment - Abstract
The CDMS and EDELWEISS collaborations have combined the results of their direct searches for dark matter using cryogenic germanium detectors. The total data set represents 614 kg.d equivalent exposure. A straightforward method of combination was chosen for its simplicity before data were exchanged between experiments. The results are interpreted in terms of limits on spin-independent WIMP-nucleon cross-section. For a WIMP mass of 90 GeV/c^2, where this analysis is most sensitive, a cross-section of 3.3 x 10^{-44} cm^2 is excluded at 90% CL. At higher WIMP masses, the combination improves the individual limits, by a factor 1.6 above 700 GeV/c^2. Alternative methods of combining the data provide stronger constraints for some ranges of WIMP masses and weaker constraints for others., Comment: Events, efficiencies, and main limit are available in text format (see README.txt)
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- 2011
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21. Search for inelastic dark matter with the CDMS II experiment
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CDMS Collaboration, Ahmed, Z., Akerib, D. S., Arrenberg, S., Bailey, C. N., Balakishiyeva, D., Baudis, L., Bauer, D. A., Brink, P. L., Bruch, T., Bunker, R., Cabrera, B., Caldwell, D. O., Cooley, J., Silva, E. do Couto e, Cushman, P., Daal, M., DeJongh, F., Di Stefano, P., Dragowsky, M. R., Duong, L., Fallows, S., Figueroa-Feliciano, E., Filippini, J., Fox, J., Fritts, M., Golwala, S. R., Hall, J., Hennings-Yeomans, R., Hertel, S. A., Holmgren, D., Hsu, L., Huber, M. E., Kamaev, O., Kiveni, M., Kos, M., Leman, S. W., Liu, S., Mahapatra, R., Mandic, V., McCarthy, K. A., Mirabolfathi, N., Moore, D., Nelson, H., Ogburn, R. W., Phipps, A., Pyle, M., Qiu, X., Ramberg, E., Rau, W., Razeti, M., Reisetter, A., Resch, R., Saab, T., Sadoulet, B., Sander, J., Schnee, R. W., Seitz, D. N., Serfass, B., Sundqvist, K. M., Tarka, M., Wikus, P., Yellin, S., Yoo, J., Young, B. A., and Zhang, J.
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Astrophysics - Cosmology and Extragalactic Astrophysics ,High Energy Physics - Experiment - Abstract
Results are presented from a reanalysis of the entire five-tower data set acquired with the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory, with an exposure of 969 kg-days. The analysis window was extended to a recoil energy of 150 keV, and an improved surface-event background-rejection cut was defined to increase the sensitivity of the experiment to the inelastic dark matter (iDM) model. Three dark matter candidates were found between 25 keV and 150 keV. The probability to observe three or more background events in this energy range is 11%. Because of the occurrence of these events the constraints on the iDM parameter space are slightly less stringent than those from our previous analysis, which used an energy window of 10-100 keV., Comment: 10 pages, 10 figures, minor changes to match published version, conclusion unchanged
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- 2010
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22. Results from a Low-Energy Analysis of the CDMS II Germanium Data
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CDMS Collaboration, Ahmed, Z., Akerib, D. S., Arrenberg, S., Bailey, C. N., Balakishiyeva, D., Baudis, L., Bauer, D. A., Brink, P. L., Bruch, T., Bunker, R., Cabrera, B., Caldwell, D. O., Cooley, J., Silva, E. do Couto e, Cushman, P., Daal, M., DeJongh, F., Di Stefano, P., Dragowsky, M. R., Duong, L., Fallows, S., Figueroa-Feliciano, E., Filippini, J., Fox, J., Fritts, M., Golwala, S. R., Hall, J., Hennings-Yeomans, R., Hertel, S. A., Holmgren, D., Hsu, L., Huber, M. E., Kamaev, O., Kiveni, M., Kos, M., Leman, S. W., Liu, S., Mahapatra, R., Mandic, V., McCarthy, K. A., Mirabolfathi, N., Moore, D., Nelson, H., Ogburn, R. W., Phipps, A., Pyle, M., Qiu, X., Ramberg, E., Rau, W., Reisetter, A., Resch, R., Saab, T., Sadoulet, B., Sander, J., Schnee, R. W., Seitz, D. N., Serfass, B., Sundqvist, K. M., Tarka, M., Wikus, P., Yellin, S., Yoo, J., Young, B. A., and Zhang, J.
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Astrophysics - Cosmology and Extragalactic Astrophysics ,High Energy Physics - Experiment - Abstract
We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from Weakly Interacting Massive Particles (WIMPs) with masses below ~10 GeV/c^2. This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9 GeV/c^2 and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments., Comment: 9 pages, 8 figures. Supplemental material included as ancillary files. v3) Added appendix with additional details regarding energy scale and backgrounds
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- 2010
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23. High throughput method to determine the surface activity of antimicrobial polymeric materials
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Wilma van Rensburg, Wikus Ernst Laubscher, and Marina Rautenbach
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Resazurin solid surface antimicrobial assay ,Science - Abstract
Surface colonization by microorganisms, combined with the rise in antibiotic resistance, is the main cause of production failures in various industries. Self-sterilising materials are deemed the best prevention of surface colonization. However, current screening methods for these sterilising materials are laborious and time-consuming. The disk diffusion antimicrobial assay and the Japanese industrial standard method for antimicrobial activity on solid surfaces, JIS Z 2801, were compared to our modified solid surface antimicrobial assay in terms of detecting the activity of antibiotic-containing cellulose disks against four bacterial pathogens. Our novel assay circumvents the long incubation times by utilising the metabolic active dye, resazurin, to shorten the time in which antibacterial results are obtained to less than 4 h. This assay allows for increased screening to identify novel sterilising materials for combatting surface colonisation. • Disk diffusion assay could only detect the activity of small compounds that leached from the material over 20–24 h. • JIS Z 2801 was also able to detect the surface activity of non-polar compounds, thought to be inactive based on the disk diffusion results. • The resazurin solid surface antimicrobial assay could obtain the same results as the JIS Z 2801, within a shorter time and in a high-throughput 96-well plate setup.
- Published
- 2021
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24. Detector Calibration for the Micro-X Sounding Rocket X-ray Telescope
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Goldfinger, D. C., Adams, J. S., Baker, R., Bandler, S. R., Bastidon, N., Danowski, M. E., Doriese, W. B., Eckart, M. E., Figueroa-Feliciano, E., Heine, S. N. T., Hilton, G. C., Hubbard, A. J. F., Kelley, R. L., Kilbourne, C. A., Manzagol-Harwood, R. E., McCammon, D., Okajima, T., Porter, F. S., Reintsema, C. D., Serlemitsos, P., Smith, S. J., and Wikus, P.
- Published
- 2018
- Full Text
- View/download PDF
25. Genetic overlap between psychotic experiences in the community across age and with psychiatric disorders
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Barkhuizen, Wikus, Pain, Oliver, Dudbridge, Frank, and Ronald, Angelica
- Published
- 2020
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26. Die /r/ in Afrikaans: Fonetiese en fonologiese eienskappe
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Daniel P. Wissing and Wikus Pienaar
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afrikaans ,rhotics ,consonants ,rhotic /r/ phoneme ,afrikaans rhotic consonants ,African languages and literature ,PL8000-8844 - Abstract
The / r / in Afrikaans: Phonetic and phonological features. One of the most common consonants in Afrikaans is the rhotic /r/ phoneme. In Afrikaans this phoneme has at least five allophone realisations. Firstly, an overview of the /r/ phoneme in Afrikaans is given. A comprehensive discussion is provided of the articulatory properties of the alveolar trill [r] and the uvular trill [ʀ]. This is followed by a discussion of the acoustical properties of [r] and [ʀ]. In-depth descriptions of the phonology of /r/ follow. Examples were taken from a variety of spoken databases. Extensive new examples are given of the phonological processes of /r/ omission, rhoticism, palatalisation, metathesis, and the influence of /r/ on the lowering and stretching of vowels. In some cases, these are complemented by audio clips. Basic statistical information is supplied about the extent to which processes are present in the standard variety of Afrikaans, and some other varieties. Secondly, we place the resultant findings concerning Afrikaans rhotic consonants within a broader linguistic framework. In 2001 Wiese encapsulates the essence of existing studies in this regard by looking into evidence of the role of rhotics as a systematic class in phonological patterning, their place in syllabic structures, and associated to that, the phonotactic unity of rhotics. The allophonic variation of rhotics, as well as the phonemic alternations thereof also gets attention. In 2009 Chabot reports that the arbitrary relation between the phonetic substance of rhotics and the associated phonological objects are devoid of any reference to phonetic categories. Our results are also in accordance with his conclusion in this regard.
- Published
- 2020
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27. Search for inelastic dark matter with the CDMS II experiment
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Ahmed, Z, Akerib, DS, Arrenberg, S, Bailey, CN, Balakishiyeva, D, Baudis, L, Bauer, DA, Brink, PL, Bruch, T, Bunker, R, Cabrera, B, Caldwell, DO, Cooley, J, do Couto e Silva, E, Cushman, P, Daal, M, DeJongh, F, Di Stefano, P, Dragowsky, MR, Duong, L, Fallows, S, Figueroa-Feliciano, E, Filippini, J, Fox, J, Fritts, M, Golwala, SR, Hall, J, Hennings-Yeomans, R, Hertel, SA, Holmgren, D, Hsu, L, Huber, ME, Kamaev, O, Kiveni, M, Kos, M, Leman, SW, Liu, S, Mahapatra, R, Mandic, V, McCarthy, KA, Mirabolfathi, N, Moore, D, Nelson, H, Ogburn, RW, Phipps, A, Pyle, M, Qiu, X, Ramberg, E, Rau, W, Razeti, M, Reisetter, A, Resch, R, Saab, T, Sadoulet, B, Sander, J, Schnee, RW, Seitz, DN, Serfass, B, Sundqvist, KM, Tarka, M, Wikus, P, Yellin, S, Yoo, J, Young, BA, and Zhang, J
- Subjects
astro-ph.CO ,hep-ex ,Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Quantum Physics ,Nuclear & Particles Physics - Abstract
Results are presented from a reanalysis of the entire five-tower data set acquired with the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory, with an exposure of 969 kg-days. The analysis window was extended to a recoil energy of 150 keV, and an improved surface-event background-rejection cut was defined to increase the sensitivity of the experiment to the inelastic dark matter (iDM) model. Three dark matter candidates were found between 25 keV and 150 keV. The probability to observe three or more background events in this energy range is 11%. Because of the occurrence of these events, the constraints on the iDM parameter space are slightly less stringent than those from our previous analysis, which used an energy window of 10-100 keV. © 2011 American Physical Society.
- Published
- 2011
28. Results from a Low-Energy Analysis of the CDMS II Germanium Data
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Ahmed, Z, Akerib, DS, Arrenberg, S, Bailey, CN, Balakishiyeva, D, Baudis, L, Bauer, DA, Brink, PL, Bruch, T, Bunker, R, Cabrera, B, Caldwell, DO, Cooley, J, do Couto e Silva, E, Cushman, P, Daal, M, DeJongh, F, Di Stefano, P, Dragowsky, MR, Duong, L, Fallows, S, Figueroa-Feliciano, E, Filippini, J, Fox, J, Fritts, M, Golwala, SR, Hall, J, Hennings-Yeomans, R, Hertel, SA, Holmgren, D, Hsu, L, Huber, ME, Kamaev, O, Kiveni, M, Kos, M, Leman, SW, Liu, S, Mahapatra, R, Mandic, V, McCarthy, KA, Mirabolfathi, N, Moore, D, Nelson, H, Ogburn, RW, Phipps, A, Pyle, M, Qiu, X, Ramberg, E, Rau, W, Reisetter, A, Resch, R, Saab, T, Sadoulet, B, Sander, J, Schnee, RW, Seitz, DN, Serfass, B, Sundqvist, KM, Tarka, M, Wikus, P, Yellin, S, Yoo, J, Young, BA, and Zhang, J
- Subjects
CDMS Collaboration ,astro-ph.CO ,hep-ex ,Mathematical Sciences ,Physical Sciences ,Engineering ,General Physics - Abstract
We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from weakly interacting massive particles (WIMPs) with masses below ∼10 GeV/c(2). This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9 GeV/c(2) and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.
- Published
- 2011
29. Correction: Strategies occupational therapists employ to facilitate work-related transitions for persons with hand injuries: a study protocol for a scoping review
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Robert Stewart, Hitesh Shetty, Rashmi Patel, Wikus Barkhuizen, Alexis E Cullen, Megan Pritchard, and Philip McGuire
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Medicine - Published
- 2020
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30. Community treatment orders and associations with readmission rates and duration of psychiatric hospital admission: a controlled electronic case register study
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Robert Stewart, Hitesh Shetty, Rashmi Patel, Wikus Barkhuizen, Alexis E Cullen, Megan Pritchard, and Philip McGuire
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Medicine - Abstract
ObjectivesLimited evidence is available regarding the effect of community treatment orders (CTOs) on mortality and readmission to psychiatric hospital. We compared clinical outcomes between patients placed on CTOs to a control group of patients discharged to voluntary community mental healthcare.Design and settingAn observational study using deidentified electronic health record data from inpatients receiving mental healthcare in South London using the Clinical Record Interactive Search (CRIS) system. Data from patients discharged between November 2008 and May 2014 from compulsory inpatient treatment under the Mental Health Act were analysed.Participants830 participants discharged on a CTO (mean age 40 years; 63% male) and 3659 control participants discharged without a CTO (mean age 42 years; 53% male).Outcome measuresThe number of days spent in the community until readmission, the number of days spent in inpatient care in the 2 years prior to and the 2 years following the index admission and mortality.ResultsThe mean duration of a CTO was 3.2 years. Patients receiving care from forensic psychiatry services were five times more likely and patients receiving a long-acting injectable antipsychotic were twice as likely to be placed on a CTO. There was a significant association between CTO receipt and readmission in adjusted models (HR: 1.60, 95% CI 1.42 to 1.80, p
- Published
- 2020
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31. Analysis of the low-energy electron-recoil spectrum of the CDMS experiment
- Author
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Ahmed, Z, Akerib, DS, Arrenberg, S, Bailey, CN, Balakishiyeva, D, Baudis, L, Bauer, DA, Beaty, J, Brink, PL, Bruch, T, Bunker, R, Cabrera, B, Caldwell, DO, Cooley, J, Cushman, P, Dejongh, F, Dragowsky, MR, Duong, L, Figueroa-Feliciano, E, Filippini, J, Fritts, M, Golwala, SR, Grant, DR, Hall, J, Hennings-Yeomans, R, Hertel, S, Holmgren, D, Hsu, L, Huber, ME, Kamaev, O, Kiveni, M, Kos, M, Leman, SW, Mahapatra, R, Mandic, V, Moore, D, McCarthy, KA, Mirabolfathi, N, Nelson, H, Ogburn, RW, Pyle, M, Qiu, X, Ramberg, E, Rau, W, Reisetter, A, Saab, T, Sadoulet, B, Sander, J, Schnee, RW, Seitz, DN, Serfass, B, Sundqvist, KM, Wang, G, Wikus, P, Yellin, S, Yoo, J, and Young, BA
- Subjects
astro-ph.GA ,astro-ph.CO ,Nuclear & Particles Physics ,Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Quantum Physics ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics - Abstract
We report on the analysis of the low-energy electron-recoil spectrum from the CDMS II experiment using data with an exposure of 443.2 kg-days. The analysis provides details on the observed counting rate and possible background sources in the energy range of 2-8.5 keV. We find no significant excess of a peaked contribution to the total counting rate above the background model, and compare this observation to the recent DAMA results. In the framework of a conversion of a dark matter particle into electromagnetic energy, our 90% confidence level upper limit of 0.246events/kg/day at 3.15 keV is lower than the total rate above background observed by DAMA. In absence of any specific particle physics model to provide the scaling in cross section between NaI and Ge, we assume a Z2 scaling. With this assumption the observed rate in DAMA remains higher than the upper limit in CDMS. Under the conservative assumption that the modulation amplitude is 6% of the total rate we obtain upper limits on the modulation amplitude a factor of ∼2 lower than observed by DAMA, constraining some possible interpretations of this modulation. © 2010 The American Physical Society.
- Published
- 2010
32. Spectral conditioning within the energy graph-based visualisation fault detection method
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Wolmarans, Wikus, van Schoor, George, and Uren, Kenneth R.
- Abstract
In an effort to improve fault detection performance, the potential of the spectral theorem as a conditioning technique is explored within an energy graph visualisation (EGBV) fault detection method. Two conditioning techniques consistent with the spectral theorem, namely, sample self-comparison and hybrid sample self-comparison, are proposed as modifications of EGBV, followed by comparison with the standard EGBV algorithm using fault data from a continuous stirred tank reactor pilot plant. The results suggest that the former and latter provide better performance compared to the standard EGBV algorithm.
- Published
- 2024
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- View/download PDF
33. Genderkompetenz in der Medizin und Osteopathie.
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Wikus, Priska and Wimpissinger, Anita
- Abstract
Bereits seit dem vorigen Jahrhundert versucht das Gender Mainstreaming, in unserer Kultur Fuß zu fassen. Ziel ist die Gleichberechtigung aller Geschlechter auf allen gesellschaftlichen Ebenen, um deren Gleichstellung durchzusetzen. Dennoch sieht man in vielen Bereichen nach wie vor den sogenannten „Gender Gap" – auch in der Medizin mit dem Gender Health Gap. Denn es zeigt sich: Der Mann steht immer noch im Zentrum (medizinischer) Forschung, ein androzentristische Weltbild und binäres Denken halten sich kontinuierlich. Für die Medizin hat dies schwerwiegende Folgen, da es oft zu Fehl- oder verspäteten Diagnosen bei anderen Geschlechtern führt: Herzerkrankungen werden bei Frauen nicht oder zu spät erkannt. Schmerzen werden tendenziell öfter ungerechtfertigt als psychosomatisch diagnostiziert, weil weibliche Personen von klein auf als empfindlich und emotional wahrgenommen werden. Nicht-binäre Personen sind nahezu nicht präsent. Medizinische Erkenntnisse zu Genderunterschieden sind auch für die Osteopathie relevant, da Symptome gendergerecht interpretiert werden müssen, um Kontraindikationen für eine Behandlung auszuschließen. Since over a century gender mainstreaming tries to take root in our society to ensure equality of all genders on all social levels. Nevertheless, the so-called gender gap is still omnipresent, especially the gender health gap. Men are still the main focus in (medical) research, the androcentric system and binary thinking are tenacious. This can cause severe consequences for medical issues for non-male genders. Late or wrong diagnosis for heart diseases or pain syndromes in women happen a lot of times because of unawareness of early symptoms or wrongly blaming a psychosomatic cause. Non-binary people are not represented at all. The medical knowledge of gender differences is also important for osteopathy, because we have to interpret those symptoms in a gender sensitive way in order to avoid missing contraindications for a treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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34. SAURAN: A new resource for solar radiometric data in Southern Africa
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Michael J Brooks, Sven du Clou, Wikus L. van Niekerk, Paul Gauché, Corli Leonard, Michael J. Mouzouris, Riaan Meyer, Nic van der Westhuizen, Ernest E. van Dyk, and Frederik J. Vorster
- Subjects
Energy conservation ,TJ163.26-163.5 ,Environmental sciences ,GE1-350 - Abstract
A new resource for sun strength data in Southern Africa has been established with the commissioning of a regional network of solar monitoring stations. The Southern African Universities Radiometric Network (SAURAN) is an initiative of Stellenbosch University and the University of KwaZulu-Natal (UKZN), and consists of an initial set of ten ground stations equipped with secondary standard thermopile radiometers. SAURAN’s aim is to provide a long-term record of sun strength in a region that shows excellent potential for the deployment of solar energy technologies. Instruments measuring direct normal irradiance (DNI), diffuse horizontal irradiance (DHI) and global horizontal irradiance (GHI) feed time-averaged data over 1-minute, hourly and daily intervals to a central archive from where they are accessible to the public via a website interface. Meteorological data is also provided by most of the stations. This paper gives a brief background to the SAURAN project and describes the network’s operation, coverage and future expansion. Examples of solar energy irradiance plots are also provided to illustrate the information available from the SAURAN database.
- Published
- 2017
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- View/download PDF
35. The Multifaceted Antibacterial Mechanisms of the Pioneering Peptide Antibiotics Tyrocidine and Gramicidin S
- Author
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Michaela Wenzel, Marina Rautenbach, J. Arnold Vosloo, Tjalling Siersma, Christopher H. M. Aisenbrey, Ekaterina Zaitseva, Wikus E. Laubscher, Wilma van Rensburg, Jan C. Behrends, Burkhard Bechinger, and Leendert W. Hamoen
- Subjects
antibiotics ,antimicrobial peptides ,bacterial cell biology ,bacterial cytological profiling ,cell membranes ,mode of action ,Microbiology ,QR1-502 - Abstract
ABSTRACT Cyclic β-sheet decapeptides from the tyrocidine group and the homologous gramicidin S were the first commercially used antibiotics, yet it remains unclear exactly how they kill bacteria. We investigated their mode of action using a bacterial cytological profiling approach. Tyrocidines form defined ion-conducting pores, induce lipid phase separation, and strongly reduce membrane fluidity, resulting in delocalization of a broad range of peripheral and integral membrane proteins. Interestingly, they also cause DNA damage and interfere with DNA-binding proteins. Despite sharing 50% sequence identity with tyrocidines, gramicidin S causes only mild lipid demixing with minor effects on membrane fluidity and permeability. Gramicidin S delocalizes peripheral membrane proteins involved in cell division and cell envelope synthesis but does not affect integral membrane proteins or DNA. Our results shed a new light on the multifaceted antibacterial mechanisms of these antibiotics and explain why resistance to them is virtually nonexistent. IMPORTANCE Cyclic β-sheet decapeptides, such as tyrocidines and gramicidin S, were among the first antibiotics in clinical application. Although they have been used for such a long time, there is virtually no resistance to them, which has led to a renewed interest in this peptide class. Both tyrocidines and gramicidin S are thought to disrupt the bacterial membrane. However, this knowledge is mainly derived from in vitro studies, and there is surprisingly little knowledge about how these long-established antibiotics kill bacteria. Our results shed new light on the antibacterial mechanism of β-sheet peptide antibiotics and explain why they are still so effective and why there is so little resistance to them.
- Published
- 2018
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- View/download PDF
36. Correction to: Genetic and Phenotypic Characteristics of a Multi-strain Probiotic for Broilers
- Author
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Neveling, Deon P., Ahire, Jayesh J., Laubscher, Wikus, Rautenbach, Marina, and Dicks, Leon M. T.
- Published
- 2020
- Full Text
- View/download PDF
37. Palatalisation of /s/ in Afrikaans
- Author
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Daan Wissing, Wikus Pienaar, and Daniel van Niekerk
- Subjects
Afrikaans, Acoustic features, Centre of Gravity, Palatalisation, /s/-Fronting, Voiceless sibilant fricatives ,Philology. Linguistics ,P1-1091 ,African languages and literature ,PL8000-8844 - Abstract
This article reports on the investigation of the acoustic characteristics of the Afrikaans voiceless alveolar fricative /s/[1]. As yet, a palatal [ʃ] for /s/ has been reported only in a limited case, namely where /s/ is followed by palatal /j/, for example in the phrase is jy (‘are you’), pronounced as [ə-ʃəi]. This seems to be an instance of regressive coarticulation, resulting in coalescence of basic /s/ and /j/. The present study revealed that, especially in the pronunciation of young, white Afrikaans-speakers, /s/ is also palatalised progressively when preceded by /r/ in the coda cluster /rs/, and, to a lesser extent, also in other contexts where /r/ is involved, for example across syllable and word boundaries. Only a slight presence of palatalisation was detected in the production of /s/ in the speech of the white, older speakers of the present study. This finding might be indicative of a definite change in the Afrikaans consonant system. A post hoc reflection is offered here on the possible presence of /s/-fronting, especially in the speech of the younger females. Such pronunciation could very well be a prestige marker for affluent speakers of Afrikaans.[1] Given that this is a study of the phonetic characteristics of the voiceless alveolar and palatal sibilant fricatives of Afrikaans, these two consonants as well as combinations thereof are presented with the phonetic symbols in square brackets [ ], except when they are specifically being dealt with in a phonemic sense, in which case the conventional slash symbols / / will be used. This is applicable to other characters too, such as the palatal fricative [j] in the next sentence. [Please click on "Supplementary files" in the ARTICLE TOOLS sidebar on the right for the accompanying video (Figure 3)]
- Published
- 2016
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38. Infusing African management philosophy into project management
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Carl Marnewick, Wikus Erasmus, and Nazeer Joseph
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project management ,African management philosophy ,Western management philosophy ,ubuntu ,decolonisation ,Management. Industrial management ,HD28-70 ,Business ,HF5001-6182 - Abstract
Orientation: The project management field of study is investigated in the context of the current debate on decolonisation of the university curriculum. Research purpose: Current project management theories and curriculum are based on Western management philosophy (WMP). This creates tension on the African continent where the debate is currently about the revival of African management philosophy (AMP) and how it should form part of management theories and the discourse in general. Motivation for the study: The problem currently is that AMP is not incorporated or even discussed within project management literature. The aim of this article is to create discussion around AMP and how it can be infused into project management theories and ultimately the curriculum. The AMP and WMP are discussed through the lens of project management, specifically the Project Management Body of Knowledge. Research design, approach and method: Philosophical discussion was employed to facilitate the discussion of infusing AMP into project management. Various historical concepts and practices were explored to provide perspective concerning management philosophies and theories. Main findings: Infusing AMP into the curriculum must be a conscientious effort from the academic staff who teach project management. Moreover, true infusion of AMP is best facilitated through the interaction between academics, students and stakeholders. There are, however, certain processes that are principle agnostic and are independent of either AMP or WMP. Practical/managerial implications: We should philosophise more on infusing AMP into project management, creating new theories, and that the curriculum should be adjusted to incorporate AMP. Contribution/value-add: This paper stimulates discussion around AMP and project management.
- Published
- 2018
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39. The new build to print design of the ITER Torus Cryopump
- Author
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Dremel, M., Pearce, R., Strobel, H., Hauer, V., Day, C., Wikus, P., and Papastergiou, S.
- Published
- 2013
- Full Text
- View/download PDF
40. Vibration Isolation Design for the Micro-X Rocket Payload
- Author
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Danowski, M. E., Heine, S. N. T., Figueroa-Feliciano, E., Goldfinger, D., Wikus, P., McCammon, D., and Oakley, P.
- Published
- 2016
- Full Text
- View/download PDF
41. Gas species, their evolution and segregation through the ITER vacuum systems
- Author
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Pearce, R.J.H., Antipenkov, A., Bersier, J.L., Boussier, B., Bryan, S., Dremel, M., Hughes, S., Sekachev, I., Worth, L., Baylor, L., Gardner, W., Meitner, S., Wikus, P., Laesser, R., and Papastergiou, S.
- Published
- 2012
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42. SASEC – the Southern African Solar Energy Conference
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Wikus van Niekerk and Alan Brent
- Subjects
Energy conservation ,TJ163.26-163.5 ,Environmental sciences ,GE1-350 - Published
- 2017
- Full Text
- View/download PDF
43. Vibration Isolation Design for the Micro-X Rocket Payload
- Author
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Heine, S. N. T., Figueroa-Feliciano, E., Rutherford, J. M., Wikus, P., Oakley, P., Porter, F. S., and McCammon, D.
- Published
- 2014
- Full Text
- View/download PDF
44. Status of the Micro-X Sounding Rocket X-Ray Spectrometer
- Author
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Goldfinger, D. C, Adams, J. S, Baker, R, Bandler, S. R, Danowski, M. E, Doriese, W. B, Eckart, M. E, Figueroa-Feliciano, E, Hilton, G. C, Hubbard, A. J. F, Kelley, R. L, Kilbourne, C. A, McCammon, D, Okajima, T, Porter, F. S, Reintsema, C. D, Serlemitsos, P, Smith, S. J, Heine, S. N. T, and Wikus, P
- Subjects
Astronomy - Abstract
Micro-X is a sounding rocket borne X-ray telescope that utilizes transition edge sensors to perform imaging spectroscopy with a high level of energy resolution. Its 2.1m focal length X-ray optic has an effective area of 300 sq cm, a field of view of 11.8 arcmin, and a bandpass of 0.12.5 keV. The detector array has 128 pixels and an intrinsic energy resolution of 4.5 eV FWHM. The integration of the system has progressed with functional tests of the detectors and electronics complete, and performance characterization of the detectors is underway. We present an update of ongoing progress in preparation for the upcoming launch of the instrument.
- Published
- 2016
- Full Text
- View/download PDF
45. A comparison of PCA and energy graph-based visualisation FDI on a heated two-tank process
- Author
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Wolmarans, Wikus, van Schoor, George, and Uren, Kenneth R.
- Abstract
In this study, the well-known Principal Component Analysis (PCA) Fault Detection and Isolation (FDI) method is compared against a recently developed hybrid FDI method, namely Energy Graph-Based Visualisation (EGBV) using twenty different process faults from a practical heated two-tank process. It was found that PCA is the more robust method as it has a lower overall False Alarm Rate (FAR), while EGBV is the superior fault isolation method. The best method for sensitive fault detection, determined using the True Alarm Rate (TAR), is dependent on the detection philosophy followed for EGBV.
- Published
- 2023
- Full Text
- View/download PDF
46. Are admission laboratory values in isolation valuable in predicting surgical outcome in patients with perforated peptic ulcers: a retrospective, cohort analytical, observational study
- Author
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Mulder, Wikus Wessel and Mulder, Wikus Wessel
- Abstract
Background: Perforated peptic ulcer carries a noteworthy mortality, and admission status is a significant prognosticator thereof. Laboratory values are objective and readily available and therefore ideal for risk stratification. The objective of the study is to calculate the predictive value of admission laboratory values in patients with perforated peptic ulcers. Methods: A retrospective, cohort analytical, observational study was performed. All patients with surgically confirmed perforated peptic ulcers at Pelonomi Tertiary Hospital from July 2014 to June 2019 were considered. Demographic data and admission laboratory values were collected from hospital and laboratory electronic databases and theatre books. Outcomes measured were in-hospital mortality, ICU admission and length of stay in ICU and in hospital. The significance of categorical variables was calculated by Chi-square and Fisher’s exact test. Logistic regression analysis considered univariately statistically significant variables. A p-value of < 0.05 was considered statistically significant. Results: Over the 5 years 188 patients met the inclusion criteria. The median age was 46 years (15-87) with a male predominance of 71.3 % (N=134). The median length of hospital stay was 7 days (1-94) and 31.4% (N=59) of patients were admitted to the Intensive Care Unit. Operative in-hospital mortality was 25.0% (N=47). Predicting the two categorical outcomes of in-hospital mortality and ICU admission abnormal haemoglobin, platelet count, urea, creatinine and potassium were all found to be statistically significant in univariate analysis. For in-hospital mortality age (OR 1.03 [95% CI 1.01-1.06]), haemoglobin (OR 4.36 [95% CI 0.98-19.39]),) and creatinine (OR 7.76 [95% CI 2.90- 20.74]),) were significant in multivariate analysis and for ICU admission age (OR 1.03 [95% CI 1.00-1.05]),), platelet count (OR2.94 [95% CI 1.24-7.01]),) and creatinine (OR 6.90 [95% CI 2.87-16.61]),). Urea ≥ 10.9mmol/L showed a sensitivity of
- Published
- 2021
47. Theoretical Models for the Cooling Power and Base Temperature of Dilution Refrigerators
- Author
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Wikus, Patrick and Niinikoski, Tapio O.
- Published
- 2010
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48. Micro-X, the TES X-ray imaging rocket: first year progress
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Wikus, P., Rutherford, J.M., Adams, J.S., Bagdasarova, Y., Bandler, S.R., Bautz, M., Boyce, K., Brown, G., Deiker, S., Doriese, W.B., Figueroa-Feliciano, E., Flanagan, K., Galeazzi, M., Hilton, G.C., Hwang, U., Irwin, K.D., Kelley, R.L., Kallman, T., Kilbourne, C.A., Kissel, S., Leman, S.W., Levine, A., Loewenstein, M., Martinez-Galarce, D., Mushotzky, R., McCammon, D., Najjar, D., Petre, R., Porter, F.S., Reintsema, C.D., Saab, T., Schulz, N., Serlemitsos, P., Smith, R., Ullom, J.N., and Yoha, K.
- Subjects
Superconducting quantum interference devices -- Design and construction ,X-ray astronomy -- Research ,Business ,Electronics ,Electronics and electrical industries - Published
- 2009
49. EURECA — the European Future of Dark Matter Searches with Cryogenic Detectors
- Author
-
Kraus, H., Bauer, M., Bavykina, I., Benoit, A., Blümer, J., Broniatowski, A., Brudanin, V., Burghart, G., Camus, P., Chantelauze, A., Chapellier, M., Chardin, G., Christ, P., Ciemniak, C., Coppi, C., De Jésus, M., De Lesquen, A., Deschamps, H., Di Stefano, P., Dumoulin, L., Eitel, K., von Feilitzsch, F., Fesquet, M., Gascon, J., Gerbier, G., Goldbach, C., Gros, M., Hauff, D., Henry, S., Horn, M., Imber, J., Isaila, C., Jochum, J., Juillard, A., Kimmerle, M., Lanfranchi, J.-C., Lemrani, R., Lubashevsky, A., Luca, M., Malek, M., Marnieros, S., McGowan, R., Mikhailik, V., Navick, X.-F., Niinikoski, T., Nollez, G., Pantic, E., Pari, P., Perevoshchikov, L., Petricca, F., Pfister, S., Potzel, W., Pröbst, F., Rau, W., Ritter, F., Rottler, K., Sanglard, V., Scholl, S., Schwamm, F., Seidel, W., Smolnikov, A., Stern, M., Teshima, M., Tolhurst, B., Westphal, W., Wikus, P., Wolf, J., and Yakushev, E.
- Published
- 2007
- Full Text
- View/download PDF
50. Charity Event der I. A. O.: 16. März 2024, Berlin.
- Author
-
Wikus, Priska
- Published
- 2024
- Full Text
- View/download PDF
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