6,021 results on '"Dewald A."'
Search Results
2. High speed neuromorphic vision-based inspection of countersinks in automated manufacturing processes
- Author
-
Salah, Mohammed, Ayyad, Abdulla, Ramadan, Mohammed, Abdulrahman, Yusra, Swart, Dewald, Abusafieh, Abdelqader, Seneviratne, Lakmal, and Zweiri, Yahya
- Published
- 2024
- Full Text
- View/download PDF
3. The impact of low-mode symmetry on inertial fusion energy output in the burning plasma state.
- Author
-
Ralph, J, Ross, J, Zylstra, A, Kritcher, A, Robey, H, Young, C, Hurricane, O, Pak, A, Callahan, D, Baker, K, Casey, D, Döppner, T, Divol, L, Hohenberger, M, Pape, S, Patel, P, Tommasini, R, Ali, S, Amendt, P, Atherton, L, Bachmann, B, Bailey, D, Benedetti, L, Berzak Hopkins, L, Betti, R, Bhandarkar, S, Biener, J, Bionta, R, Birge, N, Bond, E, Bradley, D, Braun, T, Briggs, T, Bruhn, M, Celliers, P, Chang, B, Chapman, T, Chen, H, Choate, C, Christopherson, A, Clark, D, Crippen, J, Dewald, E, Dittrich, T, Edwards, M, Farmer, W, Field, J, Fittinghoff, D, Frenje, J, Gaffney, J, Gatu Johnson, M, Glenzer, S, Grim, G, Haan, S, Hahn, K, Hall, G, Hammel, B, Harte, J, Hartouni, E, Heebner, J, Hernandez, V, Herrmann, H, Herrmann, M, Hinkel, D, Ho, D, Holder, J, Hsing, W, Huang, H, Humbird, K, Izumi, N, Jarrott, L, Jeet, J, Jones, O, Kerbel, G, Kerr, S, Khan, S, Kilkenny, J, Kim, Y, Geppert-Kleinrath, H, Geppert-Kleinrath, V, Kong, C, Koning, J, Kroll, J, Kruse, M, Kustowski, B, Landen, O, Langer, S, Larson, D, Lemos, N, Lindl, J, Ma, T, MacDonald, M, MacGowan, B, Mackinnon, A, MacLaren, S, MacPhee, A, Marinak, M, Mariscal, D, Marley, E, and Masse, L
- Abstract
Indirect Drive Inertial Confinement Fusion Experiments on the National Ignition Facility (NIF) have achieved a burning plasma state with neutron yields exceeding 170 kJ, roughly 3 times the prior record and a necessary stage for igniting plasmas. The results are achieved despite multiple sources of degradations that lead to high variability in performance. Results shown here, for the first time, include an empirical correction factor for mode-2 asymmetry in the burning plasma regime in addition to previously determined corrections for radiative mix and mode-1. Analysis shows that including these three corrections alone accounts for the measured fusion performance variability in the two highest performing experimental campaigns on the NIF to within error. Here we quantify the performance sensitivity to mode-2 symmetry in the burning plasma regime and apply the results, in the form of an empirical correction to a 1D performance model. Furthermore, we find the sensitivity to mode-2 determined through a series of integrated 2D radiation hydrodynamic simulations to be consistent with the experimentally determined sensitivity only when including alpha-heating.
- Published
- 2024
4. Disorientation as a delirium feature in non-intubated patients: development and evaluation of diagnostic accuracy of the ‘Confusion Assessment Method for Intermediate Care Unit’ (CAM-IMC) - a prospective cohort study
- Author
-
Beyer, L. P., Gathen, L. von zur, Rayah, B. El, Dewald, O., Zieschang, T., Diers, A., Ely, E. Wesley, and Guenther, U.
- Published
- 2024
- Full Text
- View/download PDF
5. Altered drug metabolism and increased susceptibility to fatty liver disease in a mouse model of myotonic dystrophy
- Author
-
Dewald, Zachary, Adesanya, Oluwafolajimi, Bae, Haneui, Gupta, Andrew, Derham, Jessica M., Chembazhi, Ullas V., and Kalsotra, Auinash
- Published
- 2024
- Full Text
- View/download PDF
6. Development of the humeral head offset index for control of humeral torsion
- Author
-
Razaeian, Sam, Husarek, Julius, Wangler, Sebastian, Dewald, Cornelia L. A., Al-Mousllie, Ibrahim, and Zhang, Dafang
- Published
- 2024
- Full Text
- View/download PDF
7. The status of academic interventional radiologists in Germany with focus on gender disparity: how can we do better?
- Author
-
Blum, Sophia Freya Ulrike, Dewald, Cornelia Lieselotte Angelika, Becker, Lena, Staudacher, Emona, Franke, Mareike, Katoh, Marcus, Hoffmann, Ralf-Thorsten, Rohde, Stefan, Paprottka, Philip Marius, Wacker, Frank, Westphalen, Kerstin, Bruners, Philipp, Gebauer, Bernhard, Das, Marco, and Uller, Wibke
- Published
- 2024
- Full Text
- View/download PDF
8. PATHFINDER-CHD: prospective registry on adults with congenital heart disease, abnormal ventricular function, and/or heart failure as a foundation for establishing rehabilitative, prehabilitative, preventive, and health-promoting measures: rationale, aims, design and methods
- Author
-
Freilinger, Sebastian, Kaemmerer, Harald, Pittrow, Robert D., Achenbach, Stefan, Baldus, Stefan, Dewald, Oliver, Ewert, Peter, Freiberger, Annika, Gorenflo, Matthias, Harig, Frank, Hohmann, Christopher, Holdenrieder, Stefan, Hörer, Jürgen, Huntgeburth, Michael, Hübler, Michael, Kohls, Niko, Klawonn, Frank, Kozlik-Feldmann, Rainer, Kaulitz, Renate, Loßnitzer, Dirk, Mellert, Friedrich, Nagdyman, Nicole, Nordmeyer, Johannes, Pittrow, Benjamin A., Pittrow, Leonard B., Rickers, Carsten, Rosenkranz, Stefan, Schelling, Jörg, Sinning, Christoph, Suleiman, Mathieu N., von Kodolitsch, Yskert, von Scheidt, Fabian, and Kaemmerer-Suleiman, Ann-Sophie
- Published
- 2024
- Full Text
- View/download PDF
9. Results of the Cologne Corona Surveillance (CoCoS) project– a cross-sectional study: survey data on risk factors of SARS-CoV-2 infection, and moderate-to-severe course in primarily immunized adults
- Author
-
Oberste, Max, Asenova, Teodora, Ernst, Angela, Shah-Hosseini, Kija, Schnörch, Nadja, Buess, Michael, Rosenberger, Kerstin Daniela, Kossow, Annelene, Dewald, Felix, Neuhann, Florian, and Hellmich, Martin
- Published
- 2024
- Full Text
- View/download PDF
10. Longitudinal Impacts of Precision Greenness on Alzheimer’s Disease
- Author
-
Brown, S. C., Aitken, W. W., Lombard, J., Parrish, A., Dewald, J. R., Ma, R., Messinger, S., Liu, S., Nardi, M. I., Rundek, T., and Szapocznik, J.
- Published
- 2024
- Full Text
- View/download PDF
11. Measurement report: Sources, sinks, and lifetime of NOx in a suburban temperate forest at night
- Author
-
S. T. Andersen, M. R. McGillen, C. Xue, T. Seubert, P. Dewald, G. N. T. E. Türk, J. Schuladen, C. Denjean, J.-C. Etienne, O. Garrouste, M. Jamar, S. Harb, M. Cirtog, V. Michoud, M. Cazaunau, A. Bergé, C. Cantrell, S. Dusanter, B. Picquet-Varrault, A. Kukui, A. Mellouki, L. J. Carpenter, J. Lelieveld, and J. N. Crowley
- Subjects
Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The budget of reactive nitrogen species, which play a central role in atmospheric chemistry (e.g. in photochemical O3 production), is poorly understood in forested regions. In this study, through observations of NO, NO2, NOy, and O3 in the Rambouillet Forest near Paris, France, we have examined nighttime processes controlling NOx in an anthropogenically impacted forest environment. The O3 mixing ratios displayed a strong diel profile at the site that was driven by a variable but generally rapid deposition to soil and foliar surfaces. The O3 diel profile was strongly influenced by relative humidity and temperature inversion. Only when the O3 mixing ratio was sufficiently low (and thus the NO lifetime sufficiently long) were sustained NO peaks observed above the instrumental detection limit, enabling the derivation of average NO emission rates of ∼1.4 ppbv h−1 from the soil. Observations of the lack of increase in NO2 at night, despite a significant production rate from the reaction of NO with O3, enabled an effective lifetime of NO2 of ∼0.5–3 h to be derived. As the loss of NO2 was not compensated for by the formation of gas- or particle-phase reactive nitrogen species, it was presumably either driven by deposition to soil and foliar surfaces or any products formed were themselves short-lived with respect to deposition. By comparison, the daytime lifetime of NO2 with respect to loss by reaction with OH is about 1 d. Our results indicate that the nighttime deposition of NO2 is a major sink of boundary layer NOx in this temperate forest environment.
- Published
- 2024
- Full Text
- View/download PDF
12. NO3 reactivity during a summer period in a temperate forest below and above the canopy
- Author
-
P. Dewald, T. Seubert, S. T. Andersen, G. N. T. E. Türk, J. Schuladen, M. R. McGillen, C. Denjean, J.-C. Etienne, O. Garrouste, M. Jamar, S. Harb, M. Cirtog, V. Michoud, M. Cazaunau, A. Bergé, C. Cantrell, S. Dusanter, B. Picquet-Varrault, A. Kukui, C. Xue, A. Mellouki, J. Lelieveld, and J. N. Crowley
- Subjects
Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
We present direct measurements of biogenic volatile organic compound (BVOC)-induced nitrate radical (NO3) reactivity (kVOC) through the diel cycle in the suburban, temperate forest of Rambouillet near Paris (France). The data were obtained in a 6-week summer period in 2022 as part of the Atmospheric ChemistRy Of the Suburban foreSt (ACROSS) campaign. kVOC was measured in a small (700 m2) clearing mainly at a height of 5.5 m above ground level but also at 40 m (for 5 d and nights). At nighttime, mean values (and 25th–75th percentile ranges) of knightVOC(5.5m) = (0.24-0.06+0.32) s−1 and knightVOC(40m) = (0.016-0.007+0.018) s−1 indicate a significant vertical gradient and low NO3 reactivity above the canopy, whereas knightVOC(5.5 m) showed peak values of up to 2 s−1 close to the ground. The strong vertical gradient in NO3 reactivity could be confirmed by measurements between 0 and 24 m on one particular night characterized by a strong temperature inversion and is a result of the decoupling of air masses aloft from the ground- and canopy-level sources of BVOCs (and nitric oxide, NO). No strong vertical gradient was observed in the mean daytime NO3 reactivity, with kdayVOC(5.5m) = (0.12 ± 0.04) s−1 for the entire campaign and kdayVOC(40m) = (0.07 ± 0.02) s−1 during the 5 d period. Within the clearing, the fractional contribution of VOCs to the total NO3 loss rate coefficient (ktot, determined by photolysis, reaction with NO and VOCs) was 80 %–90 % during the night and ∼ 50 % during the day. In terms of chemical losses of α-pinene below canopy height in the clearing, we find that at nighttime hydroxyl radicals (OH) and ozone (O3) dominate, with NO3 contributing “only” 17 %, which decreases further to 8.5 % during the day. Based on measured OH, measured O3, and calculated NO3 concentrations, the chemical lifetime of BVOCs at noon is about 1 h and is likely to be longer than timescales of transport out of the canopy (typically of the order of minutes), thus significantly reducing the importance of daytime in-canopy processing. Clearly, in forested regions where sufficient nitric oxide and nitrogen dioxide (NOx) is available, the role of NO3 and OH as initiators of BVOC oxidation is not strictly limited to nighttime and daytime, respectively, as often implied in e.g. atmospheric chemistry textbooks.
- Published
- 2024
- Full Text
- View/download PDF
13. High Speed Neuromorphic Vision-Based Inspection of Countersinks in Automated Manufacturing Processes
- Author
-
Salah, Mohammed, Ayyad, Abdulla, Ramadan, Mohammed, Abdulrahman, Yusra, Swart, Dewald, Abusafieh, Abdelqader, Seneviratne, Lakmal, and Zweiri, Yahya
- Subjects
Computer Science - Robotics - Abstract
Countersink inspection is crucial in various automated assembly lines, especially in the aerospace and automotive sectors. Advancements in machine vision introduced automated robotic inspection of countersinks using laser scanners and monocular cameras. Nevertheless, the aforementioned sensing pipelines require the robot to pause on each hole for inspection due to high latency and measurement uncertainties with motion, leading to prolonged execution times of the inspection task. The neuromorphic vision sensor, on the other hand, has the potential to expedite the countersink inspection process, but the unorthodox output of the neuromorphic technology prohibits utilizing traditional image processing techniques. Therefore, novel event-based perception algorithms need to be introduced. We propose a countersink detection approach on the basis of event-based motion compensation and the mean-shift clustering principle. In addition, our framework presents a robust event-based circle detection algorithm to precisely estimate the depth of the countersink specimens. The proposed approach expedites the inspection process by a factor of 10$\times$ compared to conventional countersink inspection methods. The work in this paper was validated for over 50 trials on three countersink workpiece variants. The experimental results show that our method provides a precision of 0.025 mm for countersink depth inspection despite the low resolution of commercially available neuromorphic cameras., Comment: 14 pages, 11 figures, 7 tables, submitted to Journal of Intelligent Manufacturing
- Published
- 2023
14. Sex and tissue-specificity of piRNA regulation in adult mice following perinatal lead (Pb) exposure
- Author
-
Bambarendage P. U. Perera, Kai Wang, Dongyue Wang, Kathleen Chen, Alisa Dewald, Swati Sriram, Jaclyn M. Goodrich, Laurie K. Svoboda, Maureen A. Sartor, and Dana C. Dolinoy
- Subjects
piRNA ,lead (Pb) ,ncRNA ,somatic ,germline ,DNA methylation ,Genetics ,QH426-470 - Abstract
Lead (Pb) is a neurotoxicant with early life exposure linked to long-term health effects. Piwi-interacting RNAs (piRNAs) are small non-coding RNAs that associate with PIWIL proteins to induce DNA methylation. It remains unknown whether Pb exposure influences piRNA expression. This study evaluated how perinatal Pb exposure (32 ppm in drinking water) impacts piRNA expression in adult mice and assessed piRNA dysregulation as a potential mechanism for Pb-induced toxicity. Pb exposure effects on piRNA expression and associated gene repression in the germline (testis/ovary) and soma (liver and brain) were evaluated. Small RNA sequencing was used to determine differentially expressed piRNAs, RT-qPCR to examine piRNA target expression, and whole genome bisulfite sequencing to evaluate target DNA methylation status. Three piRNAs (mmpiR-1500602, mmpiR-0201406, and mmpiR-0200026) were significant after multiple testing correction (all downregulated in the male Pb-exposed brain in comparison to control; FDR
- Published
- 2024
- Full Text
- View/download PDF
15. Development Of The Humeral Head Offset Index For Control Of Humeral Torsion
- Author
-
Sam Razaeian, Julius Husarek, Sebastian Wangler, Cornelia L.A. Dewald, Ibrahim Al-Mousllie, and Dafang Zhang
- Subjects
Orthopedic surgery ,RD701-811 ,Diseases of the musculoskeletal system ,RC925-935 - Published
- 2024
- Full Text
- View/download PDF
16. Near Edge Residual Stress Measurement Using Incremental Hole Drilling
- Author
-
Olson, M. D., DeWald, A. T., and Watanabe, B. T.
- Published
- 2024
- Full Text
- View/download PDF
17. PUSH AND PULL FACTORS AFFECTING DOMESTIC TOURISM IN THE ERONGO REGION, NAMIBIA
- Author
-
Ebson NGONDO, Uwe P. HERMANN, and Dewald H. VENTER
- Subjects
domestic tourists ,push factors ,pull factors ,domestic tourism ,sustainable development ,erongo region ,namibia ,Geography. Anthropology. Recreation ,Geography (General) ,G1-922 - Abstract
Despite being a well-established economic activity in numerous countries in the world, domestic tourism has received relatively little academic exploration, particularly in Namibia. While this study acknowledges the significance of work already done in this field, there remains a general lack of understanding of the factors motivating domestic tourists’ decisions to travel in the study area. As a result, this study aims to understand the key push and pull factors for domestic tourists, using the Erongo region of Namibia as a case study. The study adopts a quantitative research approach through a survey of 400 domestic tourists in the study area. Relaxation and escapism, seeking participatory experiences, and seeking enriching experiences emerged as the three main push factors, while destination attributes, events and activities, safety and familiarity, and variety of experiences were identified as dominant pull factors. The study recommends that tourism planners and marketers tailor tourism offerings to the asserted domestic tourists’ motivations to induce more domestic tourism demand and consumption among domestic tourists.
- Published
- 2024
- Full Text
- View/download PDF
18. Longitudinal Impacts of High Versus Low Greenness on Cardiovascular Disease Conditions
- Author
-
Scott C. Brown, William W. Aitken, Joanna Lombard, Abraham Parrish, Julius R. Dewald, Maria I. Nardi, Alejandro M. A. Mantero, Sarah W. Metalonis, and José Szapocznik
- Subjects
environment ,green space ,heart disease ,neighborhood greenness ,prevention ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Greenness—or vegetative presence—has been identified as a factor in chronic disease. The present study examines the longitudinal relationship between objective measures of greenness at the residential block level and incidence of 6 cardiovascular disease conditions. Methods and Results Analyses examined the impact of consistently high versus consistently low “precision” greenness at the Census block level on the 5‐year incidence of cardiovascular disease conditions, including acute myocardial infarction, atrial fibrillation, heart failure, ischemic heart disease, stroke/transient ischemic attack, and hypertension, among 229 034 US Medicare beneficiaries in Miami‐Dade County, Florida, USA. Zero‐inflated Poisson regression was used to model the odds of developing any new cardiovascular disease and number of new cardiovascular disease conditions based on greenness tertiles computed across 2011 and 2016 Normalized Difference Vegetation Index values, adjusting for individual age, sex, race, ethnicity, baseline cardiovascular disease conditions, neighborhood income, and walkability in 2011 and 2016. When compared with individuals consistently in the low greenness tertile in 2011 and 2016, those consistently in the high greenness tertile in 2011 and 2016 had a 9% lower odds of having any new cardiovascular conditions (odds ratio [OR], 0.91 [95% CI, 0.84–0.99]; P=0.021). Conclusions Over a 5‐year period, consistently high greenness, when compared with consistently low greenness, was associated with lower odds of any new cardiovascular disease conditions. Identifying the role of greenness exposure in such a small geographic area, the Census block on which the older adult resides, allows for more precise, strategic decisions on where additional trees can be added—by selecting at‐risk blocks rather than entire neighborhoods for tree‐planting interventions.
- Published
- 2024
- Full Text
- View/download PDF
19. Statutory and policy-based eco-disaster risk reduction in SADC member states
- Author
-
Alfredo A. Covele, Dewald van Niekerk, and Dirk Cilliers
- Subjects
disasters risk ,disaster risk reduction ,policies ,sadc ,eco-drr ,Risk in industry. Risk management ,HD61 - Abstract
Effective legislative framework is the cornerstone of managing hazards and disasters because they have become policy problems of global and local concern. This research study aims at understanding the implementation, strengths and gaps of policies related to Eco-DRR in SADC member states. In particular, attempts to critically analyse the making of DRM policies, as well as the variables underpinning these policies, given the high level of disaster losses. A literature survey was conducted to contextualise and conceptualise statutory and policy-based Eco-DRR. Academic literature on Eco-DRR and related policies, journal articles and related policies, official documents in SADC states including policies, acts, legislations, strategies, frameworks and plans were consulted. The analysis revealed that the Eco-DRR approaches have not yet been mainstreamed as part of standards of DRM in most of SADC member states, opting largely on ad hoc practice. Short-term plans and/or strategies don’t help to articulate funding and programme priorities. In addition, irregular updating of policies in some member states and a lack of following up mechanisms were noted. Contribution: To change this reality, it is necessary to include Eco-DRR in strategies and/or plans and to standardise ecosystem-based measures for reducing disaster risks. Additionally, there is an urgent need for empowerment of the existing institutions and creation of networks that are driven by SADC institutions. Overall, it is evident that there is a regional interest and demand to apply and standardise ecosystem-based approaches and natural or green infrastructure solutions toward Eco-DRR.
- Published
- 2024
- Full Text
- View/download PDF
20. Independent factors for the development of vasoplegic syndrome in patients undergoing coronary artery bypass surgery
- Author
-
Constantin L. Palm, Lukas Baumhove, Simon Pabst, Ulf Guenther, Malte Book, Onise Chaduneli, Andreas Martens, Friedrich Mellert, and Oliver Dewald
- Subjects
vasoplegic syndrome ,coronary artery bypass graft surgery ,Bretschneider cardioplegia ,warm blood cardioplegia ,extracorporeal circulation (ECC) ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
ObjectiveVasoplegic syndrome remains a common complication of cardiac surgery. It has serious implications for the healthcare system and individual patients, as it leads to rising healthcare costs and higher mortality. A better understanding of factors triggering vasoplegic syndrome is essential for the development of effective prevention strategies. We aimed to identify clinical characteristics and intraoperative parameters associated with the development of vasoplegic syndrome in coronary artery bypass graft surgery and the influence of vasoplegia on outcome.MethodsWe retrospectively analyzed the data of all patients who underwent isolated coronary artery bypass graft surgery or coronary artery bypass graft surgery combined with atrial appendage occlusion, using the heart-lung machine at our institution from 04/2019 to 12/2020. Vasoplegic syndrome was defined as MAP ≤60 mmHg and norepinephrine equivalence dosage of ≥0.2 μg/kg/min with a central venous saturation ≥60% within 2 days from surgery.ResultsOf 647 patients included in this study, 72 (11.1%) developed vasoplegic syndrome. Patients experiencing vasoplegia had longer stay in ICU, more frequently underwent tracheostomy and suffered more often from pneumonia. The duration of extracorporeal circulation, intraoperative application of platelet concentrates and usage of cold crystalloid cardioplegia (Bretschneider) independently predicted development of vasoplegic syndrome.ConclusionsEven in relatively low-risk cardiac surgery, vasoplegic syndrome is a common complication and was associated with serious adverse effects. The use of warm blood cardioplegia (Calafiore) seems to be safer than cold crystalloid cardioplegia (Bretschneider) and might be preferable in patients that are vulnerable to the consequences of vasoplegic syndrome.
- Published
- 2024
- Full Text
- View/download PDF
21. Beta-band cortico-muscular phase coherence in hemiparetic stroke
- Author
-
Parmar, Nishaal, Sirpal, Parikshat, Sikora, William A, Dewald, Julius P.A., Refai, Hazem H., and Yang, Yuan
- Published
- 2024
- Full Text
- View/download PDF
22. Near Surface Residual Stress Measurement Using Slotting
- Author
-
Olson, MD, Watanabe, BT, Wong, TA, DeWald, AT, and Hill, MR
- Subjects
Residual stress measurement ,Slotting method ,Measurement repeatability ,Infinite specimen dimensions ,Infinite slot length ,Residual stress comparison ,Civil Engineering ,Mechanical Engineering ,Interdisciplinary Engineering ,Mechanical Engineering & Transports - Abstract
Background: There are various experimental measurement techniques used to measure residual stress and this work describes one such method, the slotting method, and its application to measure near surface residual stresses. Objective: This work examines its application to macro-scale specimens. Methods: A series of numerical experiments were performed to understand the size required to assume that the specimen is infinitely large, namely the thickness, width, and height. To assess measurement repeatability, 12 slotting measurements were performed in a shot peened aluminum plate. Results: The numerical experiments determined the specimen should have a thickness greater than or equal to 21.6 mm (0.85 in), a total specimen width (normal to the slot length) greater than or equal to 44.5 mm (1.75 in), and total height (parallel to the slot) greater than or equal to 38.1 mm (1.5 in) for the specimen to be assumed to be infinite. Slotting measurement repeatability was found to have a maximum repeatability standard deviation of 30 MPa at the surface that decays rapidly to 5 MPa at a depth of 0.3 mm from the surface. Comparison x-ray diffraction measurements were performed. Conclusions: Infinite plate dimensions and slot length were determined as well as measurement repeatability. Slotting was shown to have significantly better repeatability than X-ray diffraction with layer removal for this application.
- Published
- 2022
23. Advances in Residual Stress Technology in Honor of Drew Nelson
- Author
-
DeWald, AT and Hill, MR
- Subjects
Civil Engineering ,Mechanical Engineering ,Interdisciplinary Engineering ,Mechanical Engineering & Transports - Published
- 2022
24. Neuromorphic Vision Based Control for the Precise Positioning of Robotic Drilling Systems
- Author
-
Ayyad, Abdulla, Halwani, Mohamad, Swart, Dewald, Muthusamy, Rajkumar, Almaskari, Fahad, and Zweiri, Yahya
- Subjects
Computer Science - Robotics ,Electrical Engineering and Systems Science - Image and Video Processing - Abstract
The manufacturing industry is currently witnessing a paradigm shift with the unprecedented adoption of industrial robots, and machine vision is a key perception technology that enables these robots to perform precise operations in unstructured environments. However, the sensitivity of conventional vision sensors to lighting conditions and high-speed motion sets a limitation on the reliability and work-rate of production lines. Neuromorphic vision is a recent technology with the potential to address the challenges of conventional vision with its high temporal resolution, low latency, and wide dynamic range. In this paper and for the first time, we propose a novel neuromorphic vision based controller for faster and more reliable machining operations, and present a complete robotic system capable of performing drilling tasks with sub-millimeter accuracy. Our proposed system localizes the target workpiece in 3D using two perception stages that we developed specifically for the asynchronous output of neuromorphic cameras. The first stage performs multi-view reconstruction for an initial estimate of the workpiece's pose, and the second stage refines this estimate for a local region of the workpiece using circular hole detection. The robot then precisely positions the drilling end-effector and drills the target holes on the workpiece using a combined position-based and image-based visual servoing approach. The proposed solution is validated experimentally for drilling nutplate holes on workpieces placed arbitrarily in an unstructured environment with uncontrolled lighting. Experimental results prove the effectiveness of our solution with an average positional errors of less than 0.1 mm, and demonstrate that the use of neuromorphic vision overcomes the lighting and speed limitations of conventional cameras., Comment: 14 pages, 11 figures, 2 tables, submitted to Robotics and Computer-Integrated Manufacturing
- Published
- 2022
25. Experiments conducted in the burning plasma regime with inertial fusion implosions
- Author
-
Ross, J. S., Ralph, J. E., Zylstra, A. B., Kritcher, A. L., Robey, H. F., Young, C. V., Hurricane, O. A., Callahan, D. A., Baker, K. L., Casey, D. T., Doeppner, T., Divol, L., Hohenberger, M., Pape, S. Le, Pak, A., Patel, P. K., Tommasini, R., Ali, S. J., Amendt, P. A., Atherton, L. J., Bachmann, B., Bailey, D., Benedetti, L. R., Hopkins, L. Berzak, Betti, R., Bhandarkar, S. D., Bionta, R. M., Birge, N. W., Bond, E. J., Bradley, D. K., Braun, T., Briggs, T. M., Bruhn, M. W., Celliers, P. M., Chang, B., Chapman, T., Chen, H., Choate, C., Christopherson, A. R., Clark, D. S., Crippen, J. W., Dewald, E. L., Dittrich, T. R., Edwards, M. J., Farmer, W. A., Field, J. E., Fittinghoff, D., Frenje, J., Gaffney, J., Johnson, M. Gatu, Glenzer, S. H., Grim, G. P., Haan, S., Hahn, K. D., Hall, G. N., Hammel, B. A., Harte, J., Hartouni, E., Heebner, J. E., Hernandez, V. J., Herrmann, H., Herrmann, M. C., Hinkel, D. E., Ho, D. D., Holder, J. P., Hsing, W. W., Huang, H., Humbird, K. D., Izumi, N., Jarrott, L. C., Jeet, J., Jones, O., Kerbel, G. D., Kerr, S. M., Khan, S. F., Kilkenny, J., Kim, Y., Kleinrath, H. Geppert, Kleinrath, V. Geppert, Kong, C., Koning, J. M., Kroll, J. J., Landen, O. L., Langer, S., Larson, D., Lemos, N. C., Lindl, J. D., Ma, T., MacDonald, M. J., MacGowan, B. J., Mackinnon, A. J., MacLaren, S. A., MacPhee, A. G., Marinak, M. M., Mariscal, D. A., Marley, E. V., Masse, L., Meaney, K., Meezan, N. B., Michel, P. A., Millot, M., Milovich, J. L., Moody, J. D., Moore, A. S., Morton, J. W., Murphy, T., Newman, K., Di Nicola, J. -M. G., Nikroo, A., Nora, R., Patel, M. V., Pelz, L. J., Peterson, J. L., Ping, Y., Pollock, B. B., Ratledge, M., Rice, N. G., Rinderknecht, H., Rosen, M., Rubery, M. S., Salmonson, J. D., Sater, J., Schiaffino, S., Schlossberg, D. J., Schneider, M. B., Schroeder, C. R., Scott, H. A., Sepke, S. M., Sequoia, K., Sherlock, M. W., Shin, S., Smalyuk, V. A., Spears, B. K., Springer, P. T., Stadermann, M., Stoupin, S., Strozzi, D. J., Suter, L. J., Thomas, C. A., Town, R. P. J., Tubman, E. R., Volegov, P. L., Weber, C. R., Widmann, K., Wild, C., Wilde, C. H., Van Wonterghem, B. M., Woods, D. T., Woodworth, B. N., Yamaguchi, M., Yang, S. T., and Zimmerman, G. B.
- Subjects
Physics - Plasma Physics ,High Energy Physics - Experiment - Abstract
An experimental program is currently underway at the National Ignition Facility (NIF) to compress deuterium and tritium (DT) fuel to densities and temperatures sufficient to achieve fusion and energy gain. The primary approach being investigated is indirect drive inertial confinement fusion (ICF), where a high-Z radiation cavity (a hohlraum) is heated by lasers, converting the incident energy into x-ray radiation which in turn drives the DT fuel filled capsule causing it to implode. Previous experiments reported DT fuel gain exceeding unity [O.A. Hurricane et al., Nature 506, 343 (2014)] and then exceeding the kinetic energy of the imploding fuel [S. Le Pape et al., Phys. Rev. Lett. 120, 245003 (2018)]. We report on recent experiments that have achieved record fusion neutron yields on NIF, greater than 100 kJ with momentary fusion powers exceeding 1PW, and have for the first time entered the burning plasma regime where fusion alpha-heating of the fuel exceeds the energy delivered to the fuel via compression. This was accomplished by increasing the size of the high-density carbon (HDC) capsule, increasing energy coupling, while controlling symmetry and implosion design parameters. Two tactics were successful in controlling the radiation flux symmetry and therefore the implosion symmetry: transferring energy between laser cones via plasma waves, and changing the shape of the hohlraum. In conducting these experiments, we controlled for known sources of degradation. Herein we show how these experiments were performed to produce record performance, and demonstrate the data fidelity leading us to conclude that these shots have entered the burning plasma regime.
- Published
- 2021
26. Search for mixed-symmetry states of nuclei in the vicinity of the double-magic nucleus 208Pb
- Author
-
Kocheva D., Stegmann R., Rainovski G., Jolie J., Pietralla N., Stahl C., Petkov P., Blazhev A., Hennig A., Bauer C., Braunroth Th., Carpenter M.P., Cortes L., Dewald A., Djongolov M., Fransen C., Gladnishki K., Janssens R.V.F., Karayonchev V., Lettmann M., Lister C.J., Litzinger J., Möller Th., Möller-Gatermann C., Scheck M., Scholz Ph., Schramm C., Thöle P., Werner V., Wölk D., Zhu S., and Van Isacker P.
- Subjects
Physics ,QC1-999 - Abstract
In this work we present the results from two experiments dedicated to search for quadrupolecollective isovector valence-shell excitation, the states with so-called mixed proton-neutron symmetry (MSS), in nuclei around the doubly magic nucleus 208Pb. 212Po was studied in an α-transfer reaction. 204Hg was studied in an inverse kinematics Coulomb excitation reaction on a carbon target. Both experiments provide indications for existence of one-phonon MSSs. Those are the first experimentally identified MSSs in the mass A ≈ 208 region.
- Published
- 2016
- Full Text
- View/download PDF
27. Lifetime measurements in mass regions A=100 and A=130 as a test for chirality in nuclear systems
- Author
-
Tonev D., Yavahchova M. S., de Angelis G., Brant S., Frauendorf S., Petkov P., Dewald A., Zhong Q., Curien D., Goutev N., Bhowmik R.K., Singh R.P., Muralithar S., Madhavan N., Kumar R., Kumar Raju M., Kaur J., Mahanto G., Singh A., Kaur N., Garg R., Sukla A., Geleva E., and Marinov Ts. K.
- Subjects
Physics ,QC1-999 - Abstract
Two odd-odd nuclei from the A ~ 100 and A ~ 130 regions, namely 102Rh and 134Pr have been studied in search for chiral doublet bands via 94Zr(11B,3n)102Rh and 119Sn(19F,4n)134Pr reactions, respectively. Two nearly degenerate bands built on the πg9/2 ⊗ vh11/2 configuration have been identified in 102Rh and on the πg11/2 ⊗ vh11/2 configuration for 134Pr. Lifetimes of excited nuclear states were measured using Dopplershift attenuation method and recoil distance Doppler-shift method. The deexciting gamma rays were registered by the Indian National Gamma Array for 102Rh and using the EUROBALL IV detector array with an inner Bismuth Germanate (BGO) ball for 134Pr, respectively. Polarization and angular correlation measurements have been performed to establish the spin and parity assignments for these bands. The derived reduced transition probabilities are compared to the predicitons of the two quasiparticles + triaxial rotor and interacting boson fermion-fermion models.
- Published
- 2016
- Full Text
- View/download PDF
28. Peripheral nerve blocks of wrist and finger flexors can increase hand opening in chronic hemiparetic stroke
- Author
-
Hendrik A. Dewald, Jun Yao, Julius P. A. Dewald, Antoun Nader, and Robert F. Kirsch
- Subjects
nerve block ,stroke ,anesthesia ,hand opening ,grasp ,FES ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
IntroductionHand opening is reduced by abnormal wrist and finger flexor activity in many individuals with stroke. This flexor activity also limits hand opening produced by functional electrical stimulation (FES) of finger and wrist extensor muscles. Recent advances in electrical nerve block technologies have the potential to mitigate this abnormal flexor behavior, but the actual impact of nerve block on hand opening in stroke has not yet been investigated.MethodsIn this study, we applied the local anesthetic ropivacaine to the median and ulnar nerve to induce a complete motor block in 9 individuals with stroke and observed the impact of this block on hand opening as measured by hand pentagonal area. Volitional hand opening and FES-driven hand opening were measured, both while the arm was fully supported on a haptic table (Unloaded) and while lifting against gravity (Loaded). Linear mixed effect regression (LMER) modeling was used to determine the effect of Block.ResultsThe ropivacaine block allowed increased hand opening, both volitional and FES-driven, and for both unloaded and loaded conditions. Notably, only the FES-driven and Loaded condition’s improvement in hand opening with the block was statistically significant. Hand opening in the FES and Loaded condition improved following nerve block by nearly 20%.ConclusionOur results suggest that many individuals with stroke would see improved hand-opening with wrist and finger flexor activity curtailed by nerve block, especially when FES is used to drive the typically paretic finger and wrist extensor muscles. Such a nerve block (potentially produced by aforementioned emerging electrical nerve block technologies) could thus significantly address prior observed shortcomings of FES interventions for individuals with stroke.
- Published
- 2024
- Full Text
- View/download PDF
29. Buried Treasure (Sven Axelrad)
- Author
-
Dewald Steyn
- Subjects
Buried Treasure ,Sven Axelrad ,speculative fiction ,ghost story ,philosophy ,death ,African languages and literature ,PL8000-8844 - Published
- 2024
- Full Text
- View/download PDF
30. Automated Feature-Specific Tree Species Identification from Natural Images using Deep Semi-Supervised Learning
- Author
-
Homan, Dewald and Preez, Johan A. du
- Subjects
Computer Science - Computer Vision and Pattern Recognition ,Statistics - Machine Learning - Abstract
Prior work on plant species classification predominantly focuses on building models from isolated plant attributes. Hence, there is a need for tools that can assist in species identification in the natural world. We present a novel and robust two-fold approach capable of identifying trees in a real-world natural setting. Further, we leverage unlabelled data through deep semi-supervised learning and demonstrate superior performance to supervised learning. Our single-GPU implementation for feature recognition uses minimal annotated data and achieves accuracies of 93.96% and 93.11% for leaves and bark, respectively. Further, we extract feature-specific datasets of 50 species by employing this technique. Finally, our semi-supervised species classification method attains 94.04% top-5 accuracy for leaves and 83.04% top-5 accuracy for bark., Comment: 21 pages, 7 figures, submitted to Ecological Informatics
- Published
- 2021
31. Non-anatomical reconstruction of chronic posterolateral corner knee injuries show failure rates from 0% to 36% versus 4.3% to 24.2% for anatomic reconstruction techniques: An updated systematic review reflecting the 2019 expert consensus statement
- Author
-
Jackson, Garrett R., Mameri, Enzo S., Condon, Joshua, DeWald, Daniel, Batra, Anjay, Salazar, Luis M., Familiari, Filippo, Matava, Matthew, Knapik, Derrick M., Verma, Nikhil N., LaPrade, Robert F., and Chahla, Jorge
- Published
- 2024
- Full Text
- View/download PDF
32. Subglacial drainage networks of the Fennoscandian Ice Sheet
- Author
-
Dewald, Nico, Livingstone, Stephen, and Clark, Chris
- Abstract
Ice sheet dynamics are modulated by subglacial meltwater, which can promote basal sliding and affect ice flow velocity. However, logistical challenges of measuring subglacial processes beneath contemporary ice sheets hinder our understanding of their spatio-temporal evolution. This thesis uses the extensive landform record of subglacial meltwater landforms in Fennoscandia to forward our understanding of the evolution of subglacial drainage networks and their relation to ice sheet retreat. Using high-resolution (2-5 m) digital elevation models, integrated networks of subglacial meltwater landforms - herein called subglacial meltwater routes - are mapped at an ice sheet-scale (~1.4 million km^2). Subglacial meltwater routes comprise eskers, tunnel valleys, subglacial meltwater channels and subglacial meltwater corridors. The analyses of >34,000 features show that subglacial meltwater routes preferentially occur in thick drift and form integrated networks. Elongated network geometries are interpreted to reflect the control of ice-surface gradients on subglacial drainage. Abrupt and laterally traceable line density changes are interpreted to record periods of greater cumulative geomorphic work during pauses in retreat. Esker enlargements - significant ridge- widenings along esker ridges - are interpreted to form due to collapse of subglacial conduits which is a potentially underestimated process during deglaciation. The orientation of subglacial meltwater routes is used to build a geometrical reconstruction of the retreat of the Fennoscandian Ice Sheet using formlines - subglacial hydrologic equipotential lines constructed perpendicular to the prevalent subglacial meltwater route direction. Cross-cutting relationships between formlines are used to disentangle the relative drainage chronology in Fennoscandia. Finally, these observations are combined with theoretical considerations to derive a conceptual model of the time-transgressive development of subglacial drainage networks during deglaciation. The model invokes progressive headward growth of subglacial meltwater routes, such that already established routes grow at the expense of other routes that become abandoned in order to sustain an efficient thread network.
- Published
- 2022
33. Measurement Layout for Residual Stress Mapping Using Slitting
- Author
-
Olson, MD, DeWald, AT, and Hill, MR
- Subjects
Residual stress measurement ,Slitting method ,Crack compliance method ,Slitting mapping ,Biaxial stress mapping ,Shear stress error ,Civil Engineering ,Mechanical Engineering ,Interdisciplinary Engineering ,Mechanical Engineering & Transports - Abstract
Background: Residual stress spatial mapping has been developed using various measurement methods, one such method comprising a multiplicity of one-dimensional slitting method measurements combined to form a two-dimensional (2D) map. However, an open question is how to best distribute the individual slitting measurements for 2D mapping. Objective: This paper investigates the efficacy of different strategies for laying out the individual slitting measurements when mapping in-plane residual stress in thin stainless steel slices removed from a larger dissimilar metal weld. Methods: Three different measurement layouts are assessed: independent measurements on nominally identical specimens (i.e., one slitting measurement per specimen, with many specimens), repeatedly bisecting a single slice, and making nominally sequential measurements from one side of the specimen towards the other side of the specimen. Additional comparison measurements are made using neutron diffraction. Results: The work shows little difference between the independent and bisecting slitting measurement layouts, and some differences with the sequential measurements. There is good general agreement between neutron diffraction measurement data and the data from the independent and bisecting layouts. Conclusions: This work suggests that when using slitting to create a 2D map of in-plane residual stress, a cutting layout that repeatedly bisects the specimen works well, requires a small number of specimens, and avoids potential errors from geometric asymmetry or measurement sequence.
- Published
- 2022
34. Real-Time Grasping Strategies Using Event Camera
- Author
-
Huang, Xiaoqian, Halwani, Mohamad, Muthusamy, Rajkumar, Ayyad, Abdulla, Swart, Dewald, Seneviratne, Lakmal, Gan, Dongming, and Zweiri, Yahya
- Subjects
Computer Science - Robotics - Abstract
Robotic vision plays a key role for perceiving the environment in grasping applications. However, the conventional framed-based robotic vision, suffering from motion blur and low sampling rate, may not meet the automation needs of evolving industrial requirements. This paper, for the first time, proposes an event-based robotic grasping framework for multiple known and unknown objects in a cluttered scene. Compared with standard frame-based vision, neuromorphic vision has advantages of microsecond-level sampling rate and no motion blur. Building on that, the model-based and model-free approaches are developed for known and unknown objects' grasping respectively. For the model-based approach, event-based multi-view approach is used to localize the objects in the scene, and then point cloud processing allows for the clustering and registering of objects. Differently, the proposed model-free approach utilizes the developed event-based object segmentation, visual servoing and grasp planning to localize, align to, and grasp the targeting object. The proposed approaches are experimentally validated with objects of different sizes, using a UR10 robot with an eye-in-hand neuromorphic camera and a Barrett hand gripper. Moreover, the robustness of the two proposed event-based grasping approaches are validated in a low-light environment. This low-light operating ability shows a great advantage over the grasping using the standard frame-based vision. Furthermore, the developed model-free approach demonstrates the advantage of dealing with unknown object without prior knowledge compared to the proposed model-based approach., Comment: 37 pages
- Published
- 2021
35. Low-lying bands with different quadrupole deformation in 155Dy
- Author
-
Petkov P., Yavahchova M.S., Möller O., Dewald A., Saha B., Fitzler A., Jessen K., Tonev D., Klug T., Heinze S., Jolie J., von Brentano P., Goutev N., Bazzacco D., Ur C. A., Farnea C. A., Axiotis M., Lunardi S., de Angelis G., Napoli D. R., Marginean N., Martinez T., and Caprio M. A.
- Subjects
Physics ,QC1-999 - Abstract
To investigate the interplay between collective and single particle degrees of freedom in odd nuclei, Recoil distance Doppler-shift and Doppler-shift attenuation lifetime measurements were carried out for levels in 155Dy in coincidence detection of gamma-rays. 26 lifetimes were determined using the Differential decay curve method. Particle plus triaxial rotor model (PTRM) calculations were performed to compare the experimental level scheme and transition strengths with theoretical ones in order to get information on the quadrupole deformation (є,γ) of the bands. As a result, different quadrupole deformations for the one-quasineutron bands at low and medium spins are deduced.
- Published
- 2014
- Full Text
- View/download PDF
36. Tests of collectivity in $^{98}$Zr by absolute transition rates
- Author
-
Karayonchev, V., Jolie, J., Blazhev, A., Dewald, A., Esmaylzadeh, A., Fransen, C., Häfner, G., Knafla, L., Litzinger, J., Müller-Gatermann, C., Régis, J. -M., Schomacker, K., Vogt, A., Warr, N., Leviatan, A., and Gavrielov, N.
- Subjects
Nuclear Experiment ,Nuclear Theory - Abstract
Lifetimes of low-spin excited states in $^{98}$Zr were measured using the recoil-distance Doppler-shift technique and the Doppler-shift attenuation method. The nucleus of interest was populated in a $^{96}$Zr($^{18}$O,$^{16}$O)$^{98}$Zr two-neutron transfer reaction at the Cologne FN Tandem accelerator. Lifetimes of six low-spin excited states, of which four are unknown, were measured. The deduced $B(E2)$ values were compared with Monte Carlo shell model and interacting boson model with configuration mixing calculations. Both approaches reproduce well most of the data but leave challenging questions regarding the structure of some low lying states., Comment: 13 pages, 12 figures, 3 tables, accepted for publication in Physical Review C
- Published
- 2021
- Full Text
- View/download PDF
37. Best Practice Guidelines for Assessment and Management of Osteoporosis in Adult Patients Undergoing Elective Spinal Reconstruction
- Author
-
Sardar, Zeeshan M, Coury, Josephine R, Cerpa, Meghan, DeWald, Christopher J, Ames, Christopher P, Shuhart, Christopher, Watkins, Colleen, Polly, David W, Dirschl, Douglas R, Klineberg, Eric O, Dimar, John R, Krohn, Kelly D, Kebaish, Khaled M, Tosi, Laura L, Kelly, Michael, Lane, Nancy E, Binkley, Neil C, Berven, Sigurd H, Lee, Nathan J, Anderson, Paul, Angevine, Peter D, Lehman, Ronald A, and Lenke, Lawrence G
- Subjects
Osteoporosis ,Aging ,Physical Injury - Accidents and Adverse Effects ,Clinical Research ,Patient Safety ,7.3 Management and decision making ,Management of diseases and conditions ,Musculoskeletal ,Absorptiometry ,Photon ,Adult ,Aged ,Bone Density ,Bone Density Conservation Agents ,Fractures ,Bone ,Humans ,Spine ,abaloparatide ,best practice ,consensus guidelines ,CT Hounsfield units ,osteoporosis ,reconstructive spine surgery ,teriparatide ,Biomedical Engineering ,Clinical Sciences ,Orthopedics - Abstract
Study designExpert consensus study.ObjectiveThis expert panel was created to establish best practice guidelines to identify and treat patients with poor bone health prior to elective spinal reconstruction.Summary of background dataCurrently, no guidelines exist for the management of osteoporosis and osteopenia in patients undergoing spinal reconstructive surgery. Untreated osteoporosis in spine reconstruction surgery is associated with higher complications and worse outcomes.MethodsA multidisciplinary panel with 18 experts was assembled including orthopedic and neurological surgeons, endocrinologists, and rheumatologists. Surveys and discussions regarding the current literature were held according to Delphi method until a final set of guidelines was created with over 70% consensus.ResultsPanelists agreed that bone health should be considered in every patient prior to elective spinal reconstruction. All patients above 65 and those under 65 with particular risk factors (chronic glucocorticoid use, high fracture risk or previous fracture, limited mobility, and eight other key factors) should have a formal bone health evaluation prior to undergoing surgery. DXA scans of the hip are preferable due to their wide availability. Opportunistic CT Hounsfield Units of the vertebrae can be useful in identifying poor bone health. In the absence of contraindications, anabolic agents are considered first line therapy due to their bone building properties as compared with antiresorptive medications. Medications should be administered preoperatively for at least 2 months and postoperatively for minimum 8 months.ConclusionBased on the consensus of a multidisciplinary panel of experts, we propose best practice guidelines for assessment and treatment of poor bone health prior to elective spinal reconstructive surgery. Patients above age 65 and those with particular risk factors under 65 should undergo formal bone health evaluation. We also established guidelines on perioperative optimization, utility of various diagnostic modalities, and the optimal medical management of bone health in this population.Level of Evidence: 5.
- Published
- 2022
38. Financing Disaster Risk Reduction: Exploring the Opportunities, Challenges, and Threats Within the Southern African Development Community Region
- Author
-
Coetzee, Christo, Khoza, Sizwile, Nemakonde, Livhuwani D., Shoroma, Lesego B., Wentink, Gideon W., Nyirenda, Maynard, Chikuse, Steven, Kamanga, Tchaka, Maripe, Kgosietsile, Rankopo, Morenaogaufi J., Mwansa, Lengwe-Katembula, and Van Niekerk, Dewald
- Published
- 2023
- Full Text
- View/download PDF
39. Effects of high-energy laser peening followed by pre-hot corrosion on stress relaxation, microhardness, and fatigue life and strength of single-crystal nickel CMSX-4® superalloy
- Author
-
Morar, Nicolau Iralal, Holtham, Noah, Hackel, Lloyd, Davami, Keivan, Sharma, Montu, DeWald, Adrian, and Roy, Rajkumar
- Published
- 2023
- Full Text
- View/download PDF
40. Effects of resilience and timing of adverse and adaptive experiences on interpersonal behavior: a transdiagnostic study in a clinical sample
- Author
-
Barbara B. Barton, Thomas Ehring, Matthias A. Reinhard, Stephan Goerigk, Torsten Wüstenberg, Richard Musil, Benedikt L. Amann, Andrea Jobst, Julia Dewald-Kaufmann, and Frank Padberg
- Subjects
Medicine ,Science - Abstract
Abstract Adverse childhood experiences (ACE) have been linked to less prosocial behavior during social exclusion in vulnerable groups. However, little is known about the impact of the timing of ACE and the roles of protective factors. Therefore, this study investigated the association of the behavioral response to experimental partial social exclusion with adverse and adaptive experiences across age groups and resilience in clinical groups with persistent depressive disorder and borderline personality disorder, i.e., groups with high ACE, and in healthy controls (HC) (N = 140). Adverse and adaptive experiences during childhood, youth, and adulthood were assessed with the Traumatic Antecedents Questionnaire, and resilience was measured with the Connor Davidson Resilience Scale. A modified version of the Cyberball paradigm was used to assess the direct behavioral response to partial social exclusion. In patients, adverse events during youth (B = − 0.12, p = 0.016) and adulthood (B = − 0.14, p = 0.013) were negatively associated with prosocial behavior, whereas in the HC sample, adaptive experiences during youth were positively associated with prosocial behavior (B = 0.25, p = 0.041). Resilience did not mediate these effects. The findings indicate that critical events during youth may be particularly relevant for interpersonal dysfunction in adulthood.
- Published
- 2023
- Full Text
- View/download PDF
41. Key factors of job satisfaction among the tourism and hospitality employees within national parks
- Author
-
Thulani M. Sibanyoni, Ndivhuwo N. Tshipala, and Dewald H. Venter
- Subjects
job satisfaction ,factors of job satisfaction ,tourism and hospitality ,service industry ,theories of job satisfaction ,Personnel management. Employment management ,HF5549-5549.5 - Abstract
Orientation: Employee job satisfaction is a widely studied concept with limited consensus on which factors of job satisfaction are most significant for tourism and hospitality employees. Specific factors of employee job satisfaction are critical to assist managers, practitioners, and academics, to enhance the levels of employee job satisfaction within national parks. Research purpose: To determine and rank the factors of job satisfaction that are most significant towards an overall job satisfaction of tourism and hospitality employees within national parks. Motivation for the study: Significant factors of job satisfaction will enable managers, practitioners, and academics to use specific factors of job satisfaction when addressing the levels of employee job satisfaction. Research approach/design and method: This article adopted a quantitative explanatory research approach using a structured e-questionnaire to collect data. The study had 211 participants. Descriptive statistics and correlation analysis were used to interpret data. Main findings: Key findings reveal that tourism and hospitality respondents within national parks have diverse demographical characteristics, and present work is among the most significant factor of job satisfaction while salary is least significant for these respondents. Practical/managerial implications: Managers and practitioners need to be specific when addressing factors of employee satisfaction. Managers need to pay more attention on employees’ present work than other factors. Contribution/value-add: This study makes a significant contribution towards the tourism employment literature because the tourism employment is associated with negative work characteristics. Managers are further provided with specific factors to measure job satisfaction.
- Published
- 2024
- Full Text
- View/download PDF
42. A postcolonial reading of the early life of Sara Baartman and the Samaritan Woman in John 4
- Author
-
Dewald E. Jacobs
- Subjects
samaritan woman ,sara baartman ,colonialism ,african biblical interpretation ,postcolonial ,intersectionality ,gender ,race ,religion ,The Bible ,BS1-2970 ,Practical Theology ,BV1-5099 - Abstract
When Jesus meets the Samaritan Woman at Jacob’s well in John 4, it is a meeting between two colonial subjects in the Roman Empire. In this encounter we find the Samaritan Woman as a triply marginalised body, a woman subject to multiple, intersecting forms of oppression within her patriarchal context. Identified as a Samaritan Woman, Jewish rabbis regarded her as unclean, impure, and being menstruous from birth. It can also be deduced that she is an outcast in her own society because she comes to draw from the well at noon, the hottest part of the day when people did not usually fetch water. This Samaritan Woman is nameless, landless and powerless in an imperial, colonial and patriarchal context. The poem of Diana Ferrus, I’ve come to take you home, in memory of Sarah Baartman, highlights how Baartman was dehumanised and treated as a sexual object by European colonisers. Through a postcolonial reading of John 4, I consider the intersections between the Samaritan Woman and the early life of Sara Baartman in their respective colonial contexts and invite the reader, as the poem invites Baartman, to come home to Africa and resist Western European imperial and colonial patterns and tendencies. Contribution: This article has interdisciplinary implications. This is an interdisciplinary study in the sense that it offers a biblical interpretation of John 4 that is informed by the life of Sara Baartman that has been uncovered through anthropology, history and sociology. It is also integrating the field of postcolonial biblical hermeneutics with the theory of intersectionality.
- Published
- 2024
- Full Text
- View/download PDF
43. Clinical Diagnosis of Scapular Dyskinesis in a Youth Softball Pitcher: A Case Report
- Author
-
Connor Skoumal and Matt Dewald
- Subjects
Sports medicine ,RC1200-1245 - Abstract
# Introduction Effective rehabilitation strategies for upper extremity injuries in softball pitchers are scarce in current literature, especially among youth athletes. Additionally, there continues to be ambiguity regarding the interpretation and clinical practicality when treating an overhead athlete with scapular dyskinesis. The purpose of this case report is to highlight the examination and treatment of a youth softball pitcher referred to physical therapy with the diagnosis of scapular dyskinesis. # Case Description This case report presents data and outcomes for a 14-year-old female who experienced chronic right shoulder discomfort related to performing the windmill softball pitch (WSP). The subject was clinically diagnosed with scapular dyskinesis by her referring physician and demonstrated abnormal scapular movement when elevating and lowering her upper extremity. Internal and external rotator isokinetic strength testing and the Athletic Shoulder Test (ASH) were used as primary objective measures. Both were performed six days after the initial evaluation and again six weeks later. Initial testing demonstrated decreased peak torque and total work. Initial treatment involved periscapular and shoulder strengthening with progression to overhead loading. Later rehabilitation strategies focused on neuromuscular control, functional training, and sport-specific activities. # Outcomes The subject initially demonstrated improved peak torque and total work of the shoulder with isokinetic strength testing but continued to have symptoms with pitching, even though the Scapular Dyskinesis Test had become negative. After changing the focus to neuromuscular and functional training the subject had fewer symptoms and became comfortable with self-management. # Discussion This case matches previous research that endorses scapular dyskinesis being a normal finding in overhead athletes with and without shoulder pain. Neuromuscular control and functional training after a period of scapular strengthening were beneficial in improving symptoms in this athlete. # Level of Evidence 5
- Published
- 2024
- Full Text
- View/download PDF
44. Isometric force pillow: using air pressure to quantify involuntary finger flexion in the presence of hypertonia
- Author
-
Seim, Caitlyn E., Han, Chuzhang, Lowber, Alexis J., Brooks, Claire, Payne, Marie, Lansberg, Maarten G., Flavin, Kara E., Dewald, Julius P. A., and Okamura, Allison M.
- Subjects
Computer Science - Robotics ,H.5.0 ,J.3 ,H.1.2 ,I.3.6 - Abstract
Survivors of central nervous system injury commonly present with spastic hypertonia. The affected muscles are hyperexcitable and can display involuntary static muscle tone and an exaggerated stretch reflex. These symptoms affect posture and disrupt activities of daily living. Symptoms are typically measured using subjective manual tests such as the Modified Ashworth Scale; however, more quantitative measures are necessary to evaluate potential treatments. The hands are one of the most common targets for intervention, but few investigators attempt to quantify symptoms of spastic hypertonia affecting the fingers. We present the isometric force pillow (IFP) to quantify involuntary grip force. This lightweight, computerized tool provides a holistic measure of finger flexion force and can be used in various orientations for clinical testing and to measure the impact of assistive devices.
- Published
- 2020
- Full Text
- View/download PDF
45. Shoulder abduction loading affects motor coordination in individuals with chronic stroke, informing targeted rehabilitation
- Author
-
Kalinowska, Aleksandra, Rudy, Kyra, Schlafly, Millicent, Fitzsimons, Kathleen, Dewald, Julius P, and Murphey, Todd D
- Subjects
Computer Science - Robotics - Abstract
Individuals post stroke experience motor impairments, such as loss of independent joint control, leading to an overall reduction in arm function. Their motion becomes slower and more discoordinated, making it difficult to complete timing-sensitive tasks, such as balancing a glass of water or carrying a bowl with a ball inside it. Understanding how the stroke-induced motor impairments interact with each other can help design assisted training regimens for improved recovery. In this study, we investigate the effects of abnormal joint coupling patterns induced by flexion synergy on timing-sensitive motor coordination in the paretic upper limb. We design a virtual ball-in-bowl task that requires fast movements for optimal performance and implement it on a robotic system, capable of providing varying levels of abduction loading at the shoulder. We recruit 12 participants (6 individuals with chronic stroke and 6 unimpaired controls) and assess their skill at the task at 3 levels of loading, defined by the vertical force applied at the robot end-effector. Our results show that, for individuals with stroke, loading has a significant effect on their ability to generate quick coordinated motion. With increases in loading, their overall task performance decreases and they are less able to compensate for ball dynamics---frequency analysis of their motion indicates that abduction loading weakens their ability to generate movements at the resonant frequency of the dynamic task. This effect is likely due to an increased reliance on lower resolution indirect motor pathways in individuals post stroke. Given the inter-dependency of loading and dynamic task performance, we can create targeted robot-aided training protocols focused on improving timing-sensitive motor control, similar to existing progressive loading therapies, which have shown efficacy for expanding reachable workspace post stroke.
- Published
- 2020
46. The first year of operation of CologneAMS; performance and developments
- Author
-
Dewald A., Heinze S., Feuerstein C., Müller-Gatermann C., Stolz A., Schiffer M., Zitzer G., Dunai T., Rethemeyer J., Melles M., Wiesel H., and Blanckenburg F. von
- Subjects
Physics ,QC1-999 - Abstract
In this contribution we report on the measurements performed so far at CologneAMS and on the quality which has been obtained for the isotopes 10Be, 14C and 26Al. We also describe the procedure developed to measure plutonium-isotopes at CologneAMS and first results for 239,240,242Pu are presented. In addition we report on modifications made on our new TOF device with beam profile capabilities.
- Published
- 2013
- Full Text
- View/download PDF
47. Heparin reversal with protamine sulfate after Percutaneous Hepatic Perfusion (PHP): is less more?
- Author
-
Facchetti, Nadia, Hinrichs, Jan B., Becker, Lena S., Schneider, Martin A., Brüning, Roland, Rademacher, Jan, Lenz, Jochen, Kudrass, Kirsten, Vogel, Arndt, Wacker, Frank K., and Dewald, Cornelia L. A.
- Published
- 2023
- Full Text
- View/download PDF
48. More anterior placement of femoral tunnel position in ACL-R is associated with postoperative meniscus tears
- Author
-
Hughes, Jonathan D., Gabrielli, Alexandra S., Dalton, Jonathan F., Raines, Benjamin T., Dewald, Daniel, Musahl, Volker, and Lesniak, Bryson P.
- Published
- 2023
- Full Text
- View/download PDF
49. Results of the Cologne Corona Surveillance (CoCoS) study – a cross-sectional study: survey data on risk factors of SARS-CoV-2 infection in adults
- Author
-
Oberste, Max, Schnörch, Nadja, Shah-Hosseini, Kija, Asenova, Teodora, Dewald, Felix, Lehmann, Clara, Buess, Michael, Fätkenheuer, Gerd, Klein, Florian, Rosenberger, Kerstin Daniela, Kossow, Annelene, Neuhann, Florian, and Hellmich, Martin
- Published
- 2023
- Full Text
- View/download PDF
50. Impaired humoral immunity to BQ.1.1 in convalescent and vaccinated patients
- Author
-
Dewald, Felix, Pirkl, Martin, Paluschinski, Martha, Kühn, Joachim, Elsner, Carina, Schulte, Bianca, Knüfer, Jacqueline, Ahmadov, Elvin, Schlotz, Maike, Oral, Göksu, Bernhard, Michael, Michael, Mark, Luxenburger, Maura, Andrée, Marcel, Hennies, Marc Tim, Hafezi, Wali, Müller, Marlin Maybrit, Kümpers, Philipp, Risse, Joachim, Kill, Clemens, Manegold, Randi Katrin, von Frantzki, Ute, Richter, Enrico, Emmert, Dorian, Monzon-Posadas, Werner O., Gräff, Ingo, Kogej, Monika, Büning, Antonia, Baum, Maximilian, Teipel, Finn, Mochtarzadeh, Babak, Wolff, Martin, Gruell, Henning, Di Cristanziano, Veronica, Burst, Volker, Streeck, Hendrik, Dittmer, Ulf, Ludwig, Stephan, Timm, Jörg, and Klein, Florian
- Published
- 2023
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.