725 results on '"Rob, F."'
Search Results
2. Towards Quantitative Magnetisation Mapping
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Remis, Rob F. and Berg, Peter M. van den
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Mathematical Physics - Abstract
The starting point in quantitative susceptibility mapping (QSM) is a theoretical model that is used to map susceptibility distributions from magnetic field measurements. It requires regularisation techniques to avoid artefacts in the resulting image. The underlying problem is that the model was developed by starting with the so-called Lorentz sphere on a microscopic scale. After averaging over a macroscopic sample, it is assumed that the magnetic flux density vanishes in the center of the sample. For the macroscopic problem of a homogeneous sphere in a uniform field, we show that at the surface the normal component of the flux density is not continuous, which contradicts Maxwell's macroscopic theory. In this paper, we propose a model consistent with macroscopic magnetic field theory, in which we image magnetisation rather than susceptibility. This model is well-posed. Some simple but representative numerical examples show that it allows for high-resolution images.
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- 2021
3. Bleeding risk from anticoagulant thromboprophylaxis in patients with multiple myeloma: a MarketScan analysis
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Adrianzen-Herrera, Diego, Giorgio, Katherine, Walker, Rob F., Sparks, Andrew D., Gergi, Mansour, Zakai, Neil A., and Lutsey, Pamela L.
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- 2024
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4. Combining Deep Learning and 3D Contrast Source Inversion in MR-based Electrical Properties Tomography
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Leijsen, Reijer L., Berg, Cornelis A. T. van den, Webb, Andrew G., Remis, Rob F., and Mandija, Stefano
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Physics - Medical Physics ,Electrical Engineering and Systems Science - Image and Video Processing - Abstract
Magnetic resonance-electrical properties tomography (MR-EPT) is a technique used to estimate the conductivity and permittivity of tissues from MR measurements of the transmit magnetic field. Different reconstruction methods are available, however all these methods present several limitations which hamper the clinical applicability. Standard Helmholtz based MR-EPT methods are severely affected by noise. Iterative reconstruction methods such as contrast source inversion-EPT (CSI-EPT) are typically time consuming and are dependent on their initialization. Deep learning (DL) based methods require a large amount of training data before sufficient generalization can be achieved. Here, we investigate the benefits achievable using a hybrid approach, i.e. using MR-EPT or DL-EPT as initialization guesses for standard 3D CSI-EPT. Using realistic electromagnetic simulations at 3 T and 7 T, the accuracy and precision of hybrid CSI reconstructions are compared to standard 3D CSI-EPT reconstructions. Our results indicate that a hybrid method consisting of an initial DL-EPT reconstruction followed by a 3D CSI-EPT reconstruction would be beneficial. DL-EPT combined with standard 3D CSI-EPT exploits the power of data driven DL-based EPT reconstructions while the subsequent CSI-EPT facilitates a better generalization by providing data consistency., Comment: 8 pages, 4 figures, 1 table
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- 2019
5. Transceive Phase Corrected Contrast Source Inversion-Electrical Properties Tomography
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Stijnman, Peter R. S., Mandija, Stefano, Fuchs, Patrick S., Berg, Cornelis A. T. van den, and Remis, Rob F.
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Physics - Medical Physics - Abstract
Magnetic resonance imaging (MRI) based electrical properties tomography (EPT) is the quantification of the conductivity and permittivity of different tissues. These electrical properties can be obtained through different reconstruction methods and can be used as a contrast mechanism. The work presented here continues from the two-dimensional CSI-EPT algorithm which was shown to work with two-dimensional Matlab based simulations. The existing CSI-EPT algorithm is reformulated to use the transceive phase rather than relying on the transceive phase assumption. This is achieved by implementing a forward problem, computing the receive phase, into the inverse minimization problem, i.e. retrieving the electrical properties. Furthermore, the radio frequency (RF) shield is numerically implemented to model the RF fields inside the MRI more accurately. Afterwards, the algorithm is tested with three-dimensional FDTD simulations to investigate if the two-dimensional CSI-EPT can retrieve the electrical properties for three-dimensional RF fields. Finally, an MR experiment with a phantom is performed to show the potential for this method. From the results of the two-dimensional Matlab simulations it is seen that CSI-EPT can reconstruct the electrical properties using MRI accessible quantities. In the three-dimensional simulations it is observed that the electrical properties are underestimated, nonetheless, CSI-EPT is more precise than the standard Helmholtz based methods. Finally, the first CSI-EPT results using measured data are shown. The results for the reconstruction using measured data were of the same quality as the results from the FDTD simulation.
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- 2019
6. SGLT2 Inhibitors Are Associated With Reduced Cardiovascular Disease in Patients With Type 2 Diabetes: An Analysis of Real-World Data
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Wang, Wendy, Chen, Lin Yee, Walker, Rob F., Chow, Lisa S., Norby, Faye L., Alonso, Alvaro, Pankow, James S., and Lutsey, Pamela L.
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- 2023
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7. Tumor-expressed factor VII is associated with survival and regulates tumor progression in breast cancer
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Kroone, Chantal, Tieken, Chris, Kocatürk, Begüm, Paauwe, Madelon, Blok, Erik J., Ünlü, Betül, van den Berg, Yascha W., Stanganello, Eliana, Kapteijn, Maaike Y., Swier, Nathalie, Zhang, Xi, Duits, Danique E. M., Lin, Yazhi, Oostenbrink, Lisa V. E., van den Akker, Rob F. P., Mosnier, Laurent O., Hawinkels, Lukas J., van Vlijmen, Bart J. M., Ruf, Wolfram, Kuppen, Peter J., Cannegieter, Suzanne C., Buijs, Jeroen T., and Versteeg, Henri H.
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- 2023
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8. Autoimmune disease and risk of postpartum venous thromboembolism
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Walker, Rob F., Zakai, Neil A., Mason, Susan M., MacLehose, Richard F., Norby, Faye L., Evensen, Line H., Alonso, Alvaro, and Lutsey, Pamela L.
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- 2023
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9. mRNA expression analysis of the hippocampus in a vervet monkey model of fetal alcohol spectrum disorder
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Rob F. Gillis and Roberta M. Palmour
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Fetal alcohol spectrum disorders ,Gene expression analysis ,Neurodevelopment ,Non-human primate model ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Abstract Background Fetal alcohol spectrum disorders (FASD) are common, yet preventable developmental disorders that stem from prenatal exposure to alcohol. This exposure leads to a wide array of behavioural and physical problems with a complex and poorly defined biological basis. Molecular investigations to date predominantly use rodent animal models, but because of genetic, developmental and social behavioral similarity, primate models are more relevant. We previously reported reduced cortical and hippocampal neuron levels in an Old World monkey (Chlorocebus sabaeus) model with ethanol exposure targeted to the period of rapid synaptogenesis and report here an initial molecular study of this model. The goal of this study was to evaluate mRNA expression of the hippocampus at two different behavioural stages (5 months, 2 years) corresponding to human infancy and early childhood. Methods Offspring of alcohol-preferring or control dams drank a maximum of 3.5 g ethanol per kg body weight or calorically matched sucrose solution 4 days per week during the last 2 months of gestation. Total mRNA expression was measured with the Affymetrix GeneChip Rhesus Macaque Genome Array in a 2 × 2 study design that interrogated two independent variables, age at sacrifice, and alcohol consumption during gestation. Results and discussion Statistical analysis identified a preferential downregulation of expression when interrogating the factor ‘alcohol’ with a balanced effect of upregulation vs. downregulation for the independent variable ‘age’. Functional exploration of both independent variables shows that the alcohol consumption factor generates broad functional annotation clusters that likely implicate a role for epigenetics in the observed differential expression, while the variable age reliably produced functional annotation clusters predominantly related to development. Furthermore, our data reveals a novel connection between EFNB1 and the FASDs; this is highly plausible both due to the role of EFNB1 in neuronal development as well as its central role in craniofrontal nasal syndrome (CFNS). Fold changes for key genes were subsequently confirmed via qRT-PCR. Conclusion Prenatal alcohol exposure leads to global downregulation in mRNA expression. The cellular interference model of EFNB1 provides a potential clue regarding how genetically susceptible individuals may develop the phenotypic triad generally associated with classic fetal alcohol syndrome.
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- 2022
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10. Effect of Chronic Digoxin Use on Mortality and Heart Failure Hospitalization in Pulmonary Arterial Hypertension
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Kevin Y. Chang, Katherine Giorgio, Katlin Schmitz, Rob F. Walker, Kurt W. Prins, Marc R. Pritzker, Stephen L. Archer, Pamela L. Lutsey, and Thenappan Thenappan
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digoxin ,heart failure ,mortality ,pulmonary hypertension ,right ventricle ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Digoxin acutely increases cardiac output in patients with pulmonary arterial hypertension (PAH) and right ventricular failure; however, the effects of chronic digoxin use in PAH are unclear. Methods and Results Data from the Minnesota Pulmonary Hypertension Repository were used. The primary analysis used likelihood of digoxin prescription. The primary end point was a composite of all‐cause mortality or heart failure (HF) hospitalization. Secondary end points included all‐cause mortality, HF hospitalization, and transplant‐free survival. Multivariable Cox proportional hazards analyses determined the hazard ratios (HR) and 95% CIs for the primary and secondary end points. Among 205 patients with PAH in the repository, 32.7% (n=67) were on digoxin. Digoxin was more often prescribed to patients with severe PAH and right ventricular failure. After propensity score‐matching, 49 patients were digoxin users, and 70 patients were nonusers; of these 31 (63.3%) in the digoxin group and 41 (58.6%) in nondigoxin group met the primary end point during a median follow‐up time of 2.1 (0.6–5.0) years. Digoxin users had a higher combined all‐cause mortality or HF hospitalization (HR, 1.82 [95% CI, 1.11–2.99]), all‐cause mortality (HR, 1.92 [95% CI, 1.06–3.49]), HF hospitalization (HR, 1.89 [95% CI, 1.07–3.35]), and worse transplant‐free survival (HR, 2.00 [95% CI, 1.12–3.58]) even after adjusting for patient characteristics and severity of PAH and right ventricular failure. Conclusions In this retrospective, nonrandomized cohort, digoxin treatment was associated with greater all‐cause mortality and HF hospitalization, even after multivariate correction. Future randomized controlled trials should assess the safety and efficacy of chronic digoxin use in PAH.
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- 2023
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11. Venous thrombosis recurrence risk according to warfarin versus direct oral anticoagulants for the secondary prevention of venous thrombosis
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Zakai, Neil A., Walker, Rob F., MacLehose, Richard F., Koh, Insu, Alonso, Alvaro, and Lutsey, Pamela L.
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- 2021
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12. Allogeneic hematopoietic stem cell transplantation in leukocyte adhesion deficiency type I and III
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Bakhtiar, Shahrzad, Salzmann-Manrique, Emilia, Blok, Henric-Jan, Eikema, Dirk-Jan, Hazelaar, Sheree, Ayas, Mouhab, Toren, Amos, Goldstein, Gal, Moshous, Despina, Locatelli, Franco, Merli, Pietro, Michel, Gerard, Öztürk, Gülyüz, Schulz, Ansgar, Heilmann, Carsten, Ifversen, Marianne, Wynn, Rob F., Aleinikova, Olga, Bertrand, Yves, Tbakhi, Abdelghani, Veys, Paul, Karakukcu, Musa, Kupesiz, Alphan, Ghavamzadeh, Ardeshir, Handgretinger, Rupert, Unal, Emel, Perez-Martinez, Antonio, Gokce, Muge, Porta, Fulvio, Aksu, Tekin, Karasu, Gülsün, Badell, Isabel, Ljungman, Per, Skorobogatova, Elena, Yesilipek, Akif, Zuckerman, Tsila, Bredius, Robbert R.G., Stepensky, Polina, Shadur, Bella, Slatter, Mary, Gennery, Andrew R., Albert, Michael H., Bader, Peter, and Lankester, Arjan
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- 2021
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13. Selective labelling of GBA2 in cells with fluorescent β-D-arabinofuranosyl cyclitol aziridines.
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Su, Qin, Louwerse, Max, Lammers, Rob F., Maurits, Elmer, Janssen, Max, Boot, Rolf G., Borlandelli, Valentina, Offen, Wendy A., Linzel, Daniël, Schröder, Sybrin P., Davies, Gideon J., Overkleeft, Herman S., Artola, Marta, and Aerts, Johannes M. F. G.
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- 2024
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14. The elephant in the room: exploring the motivational antecedents of servant leadership
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Paas, Joshua, Poell, Rob F., and Batistič, Saša
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- 2020
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15. Incidence and Risk Factors of Pulmonary Hypertension After Venous Thromboembolism: An Analysis of a Large Health Care Database
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Pamela L. Lutsey, Line H. Evensen, Thenappan Thenappan, Kurt W. Prins, Rob F. Walker, Joel F. Farley, Richard F. MacLehose, Alvaro Alonso, and Neil A. Zakai
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epidemiology ,pulmonary hypertension ,venous thromboembolism ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Pulmonary hypertension (PH) is a devastating potential complication of pulmonary embolism, a manifestation of venous thromboembolism (VTE). The incidence of and risk factors for PH in those with prior VTE are poorly characterized. Methods and Results International Classification of Diseases (ICD) codes from inpatient and outpatient medical claims from MarketScan administrative databases for years 2011 to 2018 were used to identify cases of VTE, comorbidities before the VTE event, and PH occurring subsequent to the VTE event. Cumulative incidence and hazard ratios (HR), and their 95% CI, were calculated. The 170 021 VTE cases included in the analysis were on average (±SD) 57.5±15.8 years old and 50.5% were female. A total of 5943 PH cases accrued over an average follow‐up of 1.94 years. Two years after incident VTE, the cumulative incidence (95% CI) of PH was 3.5% (3.4%–3.7%) overall. It was higher among older individuals, among women (3.9% [3.8%–4.1%]) than men (3.2% [3.0%–3.3%]), and among patients presenting with pulmonary embolism (6.2% [6.0%–6.5%]) than those presenting with deep vein thrombosis only (1.1% [1.0%–1.2%]). Adjusting for age and sex, risk of PH was higher among patients with VTE with underlying comorbidities. Using the Charlson comorbidity index, there was a dose–response relationship, whereby greater scores were associated with increased PH risk (score ≥5 versus 0: HR, (2.50 [2.30–2.71])). When evaluating individual comorbidities, the strongest associations were observed with concomitant heart failure (HR, 2.17 [2.04–2.31]), chronic pulmonary disease (2.01 [1.90–2.14]), and alcohol abuse (1.66 [1.29–2.13]). Conclusions In this large, real‐world population of insured people with VTE, 3.5% developed PH in the 2 years following their initial VTE event. Risk was higher among women, with increasing age, and in those with additional comorbidities at the time of the VTE event. These data provide insights into the burden of PH and risk factors for PH among patients with VTE.
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- 2022
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16. miRNA Expression Analysis of the Hippocampus in a Vervet Monkey Model of Fetal Alcohol Spectrum Disorder Reveals a Potential Role in Global mRNA Downregulation
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Rob F. Gillis and Roberta M. Palmour
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miRNA ,prenatal alcohol ,hippocampus ,non-human primate ,miRNA–mRNA interaction ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
MicroRNAs (miRNAs) are short-length non-protein-coding RNA sequences that post-transcriptionally regulate gene expression in a broad range of cellular processes including neuro- development and have previously been implicated in fetal alcohol spectrum disorders (FASD). In this study, we use our vervet monkey model of FASD to follow up on a prior multivariate (developmental age × ethanol exposure) mRNA analysis (GSE173516) to explore the possibility that the global mRNA downregulation we observed in that study could be related to miRNA expression and function. We report here a predominance of upregulated and differentially expressed miRNAs. Further, the 24 most upregulated miRNAs were significantly correlated with their predicted targets (Target Scan 7.2). We then explored the relationship between these 24 miRNAs and the fold changes observed in their paired mRNA targets using two prediction platforms (Target Scan 7.2 and miRwalk 3.0). Compared to a list of non-differentially expressed miRNAs from our dataset, the 24 upregulated and differentially expressed miRNAs had a greater impact on the fold changes of their corresponding mRNA targets across both platforms. Taken together, this evidence raises the possibility that ethanol-induced upregulation of specific miRNAs might contribute functionally to the general downregulation of mRNAs observed by multiple investigators in response to prenatal alcohol exposure.
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- 2023
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17. Gentamicin 240 mg plus azithromycin 2 g vs. ceftriaxone 500 mg plus azithromycin 2 g for treatment of rectal and pharyngeal gonorrhoea: a randomized controlled trial
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Rob, F., Klubalová, B., Nyčová, E., Hercogová, J., and Unemo, M.
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- 2020
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18. Single-dose cefixime 800 mg plus doxycycline 100 mg b.i.d. for 7 days compared to single-dose ceftriaxone 1 g plus single-dose azithromycin 2 g for treatment of urogenital, rectal and pharyngeal gonorrhoea : A randomised clinical trial
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Bížová, B., Procházka, P., Nyčová, E., Bořil, P., Kubele, J., Poláková, A., Zemanová, Z., Unemo, Magnus, Rob, F., Bížová, B., Procházka, P., Nyčová, E., Bořil, P., Kubele, J., Poláková, A., Zemanová, Z., Unemo, Magnus, and Rob, F.
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OBJECTIVES: To evaluate the efficacy and tolerability of single-dose oral cefixime 800 mg plus oral doxycycline 100 mg b.i.d. for 7 days, compared to recommended single-dose ceftriaxone plus single-dose, oral azithromycin, for treatment of uncomplicated urogenital, rectal or pharyngeal gonorrhoea. METHODS: A non-inferiority, open-label, multicentre randomised controlled trial was conducted in Prague, Czech Republic. Some 161 patients, 18-65 years of age diagnosed with uncomplicated urogenital, rectal or pharyngeal gonorrhoea by nucleic acid amplification test (NAAT) were randomised to treatment with single-dose cefixime 800 mg plus doxycycline 100 mg b.i.d. for 1 week or single-dose ceftriaxone 1 g intramuscularly plus single-dose azithromycin 2 g. The primary outcome was the number of participants with negative culture and NAAT at 1 week and 3 weeks, respectively, after treatment initiation. RESULTS: In all, 161 patients were randomised, 152 were included in per-protocol analyses. All 76 (100%; 95% confidence interval [CI], 0.95-1.00) patients treated with ceftriaxone plus azithromycin achieved negative cultures and NAAT after treatment. In the cefixime plus doxycycline arm at week 1, culture was negative in all 76 (100%) patients; at week 3, culture was negative in 70/76 patients (92%; 95%CI, 0.84-0.97) and NAAT negative in 66/76 patients (87%; 95%CI, 0.77-0.94). At week 3, culture and NAAT were negative in 65/76 patients (86%; 95%CI, 0.76-0.93). Per-protocol risk difference was 14.5% (95%CI, 6.56-22.38). All treatment failures observed in the cefixime arm were pharyngeal gonorrhoea cases. CONCLUSION: The combination of cefixime and doxycycline did not achieve non-inferiority to ceftriaxone and azithromycin for treatment of gonorrhoea when including pharyngeal gonorrhoea. It did, however, show high efficacy for urogenital and rectal gonorrhoea.
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- 2024
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19. Correction: Meaningful work and resilience among teachers: The mediating role of work engagement and job crafting.
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Sophie Groot Wassink, Jessica van Wingerden, and Rob F Poell
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Medicine ,Science - Abstract
[This corrects the article DOI: 10.1371/journal.pone.0222518.].
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- 2022
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20. Pigeonholing or Learning Instrument?: Test Takers' Reactions to Personality Testing in Management Development
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Lundgren, Henriette, Kroon, Brigitte, and Poell, Rob F.
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Purpose: While factors that influence test takers' reactions to personality testing in selection contexts have been well researched, little empirical research evidence exists to determine whether these factors also apply to test takers' reactions in the context of management development (MD). The purpose of this study is, therefore, to explore what explains different test takers' reactions in the context of MD programs. Design/methodology/approach: A qualitative longitudinal approach with three phases of data collection was used, resulting in participatory workshop observations and 11 semi-structured interviews with participants from two different contexts. Data were analyzed using Qualitative Comparative Analysis (QCA). Findings: The findings show that test takers' reactions vary; some are more accepting, others are more neutral or rejecting, where perceived usefulness, clarity of purpose and perceived respectfulness are identified as distinguishing factors. Individuals also differ in terms of their awareness of assumptions and their perceived emotional safety, two emerging factors that are relevant in the MD context. Research limitations/implications: Data were collected during the MD workshops and three months after, but no records of immediate test takers' reactions were included, which could be an addition for future research. Practical implications: The findings of this study suggest that human resource development (HRD) professionals have significant impact on test takers' reactions when it comes to encouraging self-reflection and learning along personality tests. Originality/value: This study adds to existing research by offering insights into factors in MD settings where participants are concerned about aspects of fairness, learning and behavioral change.
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- 2019
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21. Teachers' Goal Orientation Profiles and Participation in Professional Development Activities
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Kunst, Eva M., van Woerkom, Marianne, and Poell, Rob F.
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Participation in professional development activities is important for teachers to continuously improve their knowledge and skills. However, teachers differ in their attitude towards learning activities. This paper examined how different goal orientation profiles are related to participation in professional development activities (acquiring information and asking feedback). To this end, we conducted latent profile analysis based on a sample of 984 teachers in vocational education. Five profiles were identified: diffuse (50.1%), moderate learning (12.3%), high avoidance (10.9%), performance oriented (15.9%) and success oriented (10.7%). Furthermore, means of acquiring information and asking feedback from teachers were compared across the profiles. Teachers with a success-oriented profile (high learning and performance approach goals) scored significantly higher while teachers with a high-avoidance profile scored significantly lower on asking for feedback and acquiring information. Exploration of background characteristics indicated that age, gender and work experience outside education were related to the goal orientation profiles. Our findings show that goal orientation profiles can be used to explain individual differences in teachers' propensity to engage in professional development activities.
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- 2018
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22. The Contribution of Social Networks to Individual Learning in Service Organizations
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Poell, Rob F. and Van der Krogt, Ferd J.
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This study investigates how social networks in service organizations contribute to employee learning. Two specific types of social network seem especially relevant to individual learning: first, the service network, where employees carry out and improve their work, which may lead to learning; and second, the learning network, where employees participate in intentional programs in order to learn. Their experiences acting in both networks can help employees create their own learning paths in the workplace. (Contains 3 figures and 2 tables.)
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- 2007
23. Towards Further Development of HRD as an Academic Discipline: Comparing HRD Research Published in HRD and Mainstream Journals
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Wasti, S. Arzu and Poell, Rob F.
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This study reviews 125 HRD-focused articles published in two major HRD journals and ten mainstream SSCI journals across a six-year timeframe (1998-2003). It compares theoretical frameworks and methodologies employed in these different outlets, also looking at differences between US and European articles. Several differences in theoretical perspectives emerged. Methodology in US and mainstream journals was deemed more rigorous than in European and HRD journals. Generally, US/European differences were more prominent than HRD/mainstream ones.
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- 2006
24. Reduction of oxidative stress suppresses poly-GR-mediated toxicity in zebrafish embryos
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Fréderike W. Riemslagh, Rob F. M. Verhagen, Esmay C. van der Toorn, Daphne J. Smits, Wim H. Quint, Herma C. van der Linde, Tjakko J. van Ham, and Rob Willemsen
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c9orf72 ,amyotrophic lateral sclerosis ,frontotemporal dementia ,poly-gr ,neurodegeneration ,oxidative stress ,Medicine ,Pathology ,RB1-214 - Abstract
The hexanucleotide (G4C2)-repeat expansion in the C9ORF72 gene is the most common pathogenic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). This repeat expansion can be translated into dipeptide repeat proteins (DPRs), and distribution of the poly-GR DPR correlates with neurodegeneration in postmortem C9FTD/ALS brains. Here, we assessed poly-GR toxicity in zebrafish embryos, using an annexin A5-based fluorescent transgenic line (secA5) that allows for detection and quantification of apoptosis in vivo. Microinjection of RNA encoding poly-GR into fertilized oocytes evoked apoptosis in the brain and abnormal motor neuron morphology in the trunk of 1-4-days postfertilization embryos. Poly-GR can be specifically detected in protein homogenates from injected zebrafish and in the frontal cortexes of C9FTD/ALS cases. Poly-GR expression further elevated MitoSOX levels in zebrafish embryos, indicating oxidative stress. Inhibition of reactive oxygen species using Trolox showed full suppression of poly-GR toxicity. Our study indicates that poly-GR can exert its toxicity via oxidative stress. This zebrafish model can be used to find suppressors of poly-GR toxicity and identify its molecular targets underlying neurodegeneration observed in C9FTD/ALS.
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- 2021
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25. Cross-Cultural Multi-Theory Perspectives in Research: Dialogue Based on Theory and Data from the US and the Netherlands on Action Learning Programs
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Poell, Rob F., Yorks, Lyle, Marsick, Victoria J., and Woodall, Jean
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This innovative session consists of a panel discussion on different approaches to researching and understanding action-learning programs, based on collaborative empirical work. Panel members compare their use of a critical-pragmatist approach and an actor-network approach. These different but complementary approaches are compared regarding their focus on managers vs. shop floor employees, the role of the set facilitator, implementation and continuation of learning following the program, and the integration of work and (self-directed) learning. [For complete proceedings, see ED491481.]
- Published
- 2004
26. Direct oral anticoagulants and warfarin for venous thromboembolism treatment: Trends from 2012 to 2017
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Pamela L. Lutsey, Rob F. Walker, Richard F. MacLehose, Alvaro Alonso, Terrence J. Adam, and Neil A. Zakai
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apixaban ,direct oral anticoagulants ,prescription trends ,rivaroxaban ,venous thromboembolism ,warfarin ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Abstract Background Direct oral anticoagulants (DOACs), namely rivaroxaban, apixaban, dabigatran, and edoxaban, are now included together with warfarin as standards of care for the primary treatment of venous thromboembolism (VTE). The extent to which the DOACs have been adopted since receiving US Food and Drug Administration (FDA) approval is unknown. Objective To document temporal trends in oral anticoagulant (OAC) prescriptions among anticoagulant‐naïve patients initiating OACs for VTE primary treatment in the United States and to report participant characteristics by OAC prescribed for the year 2017. Methods MarketScan databases for years 2012 through 2017 were used to identify VTE cases and comorbidities using International Classification of Diseases codes and prescriptions for OACs via outpatient pharmaceutical claims data. Results The 137 203 VTE cases were on average (± standard deviation) 56.7 ± 16.0 years old and 49.9% female. Warfarin was prescribed to 98.7% of VTE patients receiving an OAC in quarter 1 (January through March) of 2012. By quarter 4 (October through December) of 2017, warfarin was prescribed to 17.5%, while rivaroxaban was prescribed to 42.7%, apixaban to 38.6%, dabigatran to 1.3%, and edoxaban to
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- 2019
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27. A zwitterionic near-infrared fluorophore for real-time ureter identification during laparoscopic abdominopelvic surgery
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Kim S. de Valk, Henricus J. Handgraaf, Marion M. Deken, Babs G. Sibinga Mulder, Adrianus R. Valentijn, Anton G. Terwisscha van Scheltinga, Joeri Kuil, Michiel J. van Esdonk, Jaap Vuijk, Rob F. Bevers, Koen C. Peeters, Fabian A. Holman, John V. Frangioni, Jacobus Burggraaf, and Alexander L. Vahrmeijer
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Science - Abstract
Iatrogenic injury of the ureters is a feared complication of laparoscopic abdominal surgery. Here the authors present the NIR fluorophore ZW800-1 as an intraoperative imaging agent for ureter mapping, showing its safety, pharmacokinetic properties, and efficacy in healthy volunteers and patients undergoing abdominopelvic surgery.
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- 2019
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28. Claims‐Based Score for the Prediction of Bleeding in a Contemporary Cohort of Patients Receiving Oral Anticoagulation for Venous Thromboembolism
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Alvaro Alonso, Faye L. Norby, Richard F. MacLehose, Neil A. Zakai, Rob F. Walker, Terrence J. Adam, and Pamela L. Lutsey
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bleeding ,MarketScan ,oral anticoagulants ,prediction ,venous thromboembolism ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Current scores for bleeding risk assessment in patients with venous thromboembolism (VTE) undergoing oral anticoagulation have limited predictive capacity. We developed and internally validated a bleeding prediction model using healthcare claims data. Methods and Results We selected patients with incident VTE initiating oral anticoagulation in the 2011 to 2017 MarketScan databases. Hospitalized bleeding events were identified using validated algorithms in the 180 days after VTE diagnosis. We evaluated demographic factors, comorbidities, and medication use before oral anticoagulation initiation as potential predictors of bleeding using stepwise selection of variables in Cox models run on 1000 bootstrap samples of the patient population. Variables included in >60% of all models were selected for the final analysis. We internally validated the model using bootstrapping and correcting for optimism. We included 165 434 patients with VTE and initiating oral anticoagulation, of whom 2294 had a bleeding event. After undergoing the variable selection process, the final model included 20 terms (15 main effects and 5 interactions). The c‐statistic for the final model was 0.68 (95% CI, 0.67–0.69). The internally validated c‐statistic corrected for optimism was 0.68 (95% CI, 0.67–0.69). For comparison, the c‐statistic of the Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile International Normalized Ratio, Elderly (>65 Years), Drugs/Alcohol Concomitantly (HAS‐BLED) score in this population was 0.62 (95% CI, 0.61–0.63). Conclusions We have developed a novel model for bleeding prediction in VTE using large healthcare claims databases. Performance of the model was moderately good, highlighting the urgent need to identify better predictors of bleeding to inform treatment decisions.
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- 2021
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29. Design, Characterisation and Performance of an Improved Portable and Sustainable Low-Field MRI System
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Bart de Vos, Javad Parsa, Zaynab Abdulrazaq, Wouter M. Teeuwisse, Camille D. E. Van Speybroeck, Danny H. de Gans, Rob F. Remis, Tom O’Reilly, and Andrew G. Webb
- Subjects
low field MRI ,MR hardware ,halbach magnet ,gradient coil design ,RF coil array ,RF amplifier ,Physics ,QC1-999 - Abstract
Low-field permanent magnet-based MRI systems are finding increasing use in portable, sustainable and point-of-care applications. In order to maximize performance while minimizing cost many components of such a system should ideally be designed specifically for low frequency operation. In this paper we describe recent developments in constructing and characterising a low-field portable MRI system for in vivo imaging at 50 mT. These developments include the design of i) high-linearity gradient coils using a modified volume-based target field approach, ii) phased-array receive coils, and iii) a battery-operated three-axis gradient amplifier for improved portability and sustainability. In addition, we report performance characterisation of the RF amplifier, the gradient amplifier, eddy currents from the gradient coils, and describe a quality control protocol for the overall system.
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- 2021
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30. Impact of oral anticoagulant choice for the secondary prevention of venous thromboembolism on the risk of inpatient bleeding
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Richard F. MacLehose, Neil A. Zakai, Rob F. Walker, Alvaro Alonso, Terrence Adams, and Pamela L. Lutsey
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Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
Abstract Background Randomized trials suggest that direct oral anticoagulants (DOACs) are at least as effective as warfarin for primary treatment of VTE and that bleeding risk may be lower for some DOACs relative to warfarin. However, there is very little information regarding potential bleeding risks for DOACs versus warfarin in secondary prevention of VTE. Objective The aim of this study was to compare rates of bleeding events resulting in inpatient admissions between individuals taking apixaban, rivaroxaban, and warfarin for secondary prevention of VTE during the period 2013‐2017. Methods We used the IBM MarketScan Commercial Claims and Encounters Database and Medicare Supplemental and Coordination of Benefits Database (IBM Watson Health, Ann Arbor, MI) to establish a retrospective cohort. Initial venous thrombolism events were defined from medical claims, and follow‐up for this cohort began 6 months after the initial event. Bleeding events resulting in inpatient admission were identified from claims data over the subsequent year of secondary prevention. Results A total of 69 264 individuals were identified for the cohort, with 567 bleeding events. The crude rate of bleeding was highest among warfarin users (1.47/100 person‐years; 95% confidence interval [CI], 1.24‐1.74) and lower among those on either apixaban (1.00/100 person‐years; 95% CI, 0.65‐1.54) or rivaroxaban (0.84/100 person‐years; 95% CI, 0.66‐1.08). In multivariable adjusted Cox models, those on apixaban (hazard ratio [HR], 0.80; 95% CI, 0.50‐1.29) and rivaroxaban (HR, 0.81; 95% CI, 0.59‐1.09) had somewhat lower rates of bleeding events relative to those on warfarin. Conclusions We found modest evidence of decreased risk of bleeding for apixaban and rivaroxaban. These estimates were relatively imprecise.
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- 2021
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31. Effect of Weight and Maturation on Busulfan Clearance in Infants and Small Children Undergoing Hematopoietic Cell Transplantation
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Savic, Radojka M, Cowan, Morton J, Dvorak, Christopher C, Pai, Sung-Yun, Pereira, Luis, Bartelink, Imke H, Boelens, Jaap J, Bredius, Robbert GM, Wynn, Rob F, Cuvelier, Geoff DE, Shaw, Peter J, Slatter, Mary A, and Long-Boyle, Janel
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Pharmacology and Pharmaceutical Sciences ,Biomedical and Clinical Sciences ,Transplantation ,Pediatric ,Perinatal Period - Conditions Originating in Perinatal Period ,Clinical Research ,Good Health and Well Being ,Antineoplastic Agents ,Alkylating ,Busulfan ,Child ,Preschool ,Female ,Hematopoietic Stem Cell Transplantation ,Humans ,Infant ,Infant ,Newborn ,Male ,Retrospective Studies ,Transplantation Conditioning ,Transplantation ,Autologous ,Hematopoietic cell transplantation ,Pharmacokinetics ,Pediatrics ,Clinical Sciences ,Immunology ,Cardiovascular medicine and haematology - Abstract
Little information is currently available regarding the pharmacokinetics (PK) of busulfan in infants and small children to help guide decisions for safe and efficacious drug therapy. The objective of this study was to develop an algorithm for individualized dosing of i.v. busulfan in infants and children weighing ≤12 kg, that would achieve targeted exposure with the first dose of busulfan. Population PK modeling was conducted using intensive time-concentration data collected through the routine therapeutic drug monitoring of busulfan in 149 patients from 8 centers. Busulfan PK was well described by a 1-compartment base model with linear elimination. The important clinical covariates affecting busulfan PK were actual body weight and age. Based on our model, the predicted clearance of busulfan increases approximately 1.7-fold between 6 weeks to 2 years of life. For infants age
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- 2013
32. Minimizing Cache Misses in Scientific Computing Using Isoperimetric Bodies
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Frumkin, Michael and Van der Wijngaart, Rob F.
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Computer Science - Performance ,C.4 ,B.8 - Abstract
A number of known techniques for improving cache performance in scientific computations involve the reordering of the iteration space. Some of these reorderings can be considered coverings of the iteration space with sets having small surface-to-volume ratios. Use of such sets may reduce the number of cache misses in computations of local operators having the iteration space as their domain. First, we derive lower bounds on cache misses that any algorithm must suffer while computing a local operator on a grid. Then, we explore coverings of iteration spaces of structured and unstructured discretization grid operators which allow us to approach these lower bounds. For structured grids we introduce a covering by successive minima tiles based on the interference lattice of the grid. We show that the covering has a small surface-to-volume ratio and present a computer experiment showing actual reduction of the cache misses achieved by using these tiles. For planar unstructured grids we show existence of a covering which reduces the number of cache misses to the level of that of structured grids. Next, we introduce a class of multidimensional grids, called starry grids in this paper. These grids represent an abstraction of unstructured grids used in, for example, molecular simulations and the solution of partial differential equations. We show that starry grids can be covered by sets having a low surface-to-volume ratio and, hence have the same cache efficiency as structured grids. Finally, we present a triangulation of a three-dimensional cube that has the property that any local operator on the corresponding grid must incur a significantly larger number of cache misses than a similar operator on a structured grid of the same size., Comment: 27 pages, 10 figures
- Published
- 2002
33. Neuropathology in mouse models of mucopolysaccharidosis type I, IIIA and IIIB.
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Wilkinson, Fiona L, Holley, Rebecca J, Langford-Smith, Kia J, Badrinath, Soumya, Liao, Aiyin, Langford-Smith, Alex, Cooper, Jonathan D, Jones, Simon A, Wraith, J Ed, Wynn, Rob F, Merry, Catherine LR, and Bigger, Brian W
- Subjects
Parietal Lobe ,Somatosensory Cortex ,Neurons ,Lysosomes ,Animals ,Mice ,Mucopolysaccharidosis I ,Mucopolysaccharidosis III ,Disease Models ,Animal ,Disease Progression ,G(M2) Ganglioside ,Glycosaminoglycans ,Heparitin Sulfate ,Carrier Proteins ,Cytokines ,Immunohistochemistry ,Female ,Male ,Vesicle-Associated Membrane Protein 2 ,Homer Scaffolding Proteins ,Disease Models ,Animal ,General Science & Technology - Abstract
Mucopolysaccharide diseases (MPS) are caused by deficiency of glycosaminoglycan (GAG) degrading enzymes, leading to GAG accumulation. Neurodegenerative MPS diseases exhibit cognitive decline, behavioural problems and shortened lifespan. We have characterised neuropathological changes in mouse models of MPSI, IIIA and IIIB to provide a better understanding of these events.Wild-type (WT), MPSI, IIIA and IIIB mouse brains were analysed at 4 and 9 months of age. Quantitative immunohistochemistry showed significantly increased lysosomal compartment, GM2 ganglioside storage, neuroinflammation, decreased and mislocalised synaptic vesicle associated membrane protein, (VAMP2), and decreased post-synaptic protein, Homer-1, in layers II/III-VI of the primary motor, somatosensory and parietal cortex. Total heparan sulphate (HS), was significantly elevated, and abnormally N-, 6-O and 2-O sulphated compared to WT, potentially altering HS-dependent cellular functions. Neuroinflammation was confirmed by significantly increased MCP-1, MIP-1α, IL-1α, using cytometric bead arrays. An overall genotype effect was seen in all parameters tested except for synaptophysin staining, neuronal cell number and cortical thickness which were not significantly different from WT. MPSIIIA and IIIB showed significantly more pronounced pathology than MPSI in lysosomal storage, astrocytosis, microgliosis and the percentage of 2-O sulphation of HS. We also observed significant time progression of all genotypes from 4-9 months in lysosomal storage, astrocytosis, microgliosis and synaptic disorganisation but not GM2 gangliosidosis. Individual genotype*time differences were disparate, with significant progression from 4 to 9 months only seen for MPSIIIB with lysosomal storage, MPSI with astrocytocis and MPSIIIA with microgliosis as well as neuronal loss. Transmission electron microscopy of MPS brains revealed dystrophic axons, axonal storage, and extensive lipid and lysosomal storage. These data lend novel insight to MPS neuropathology, suggesting that MPSIIIA and IIIB have more pronounced neuropathology than MPSI, yet all are still progressive, at least in some aspects of neuropathology, from 4-9 months.
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- 2012
34. Inducible expression of human C9ORF72 36× G4C2 hexanucleotide repeats is sufficient to cause RAN translation and rapid muscular atrophy in mice
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Fréderike W. Riemslagh, Esmay C. van der Toorn, Rob F. M. Verhagen, Alex Maas, Laurens W. J. Bosman, Renate K. Hukema, and Rob Willemsen
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c9orf72 ,als ,ftd ,mouse ,inducible ,dprs ,Medicine ,Pathology ,RB1-214 - Abstract
The hexanucleotide G4C2 repeat expansion in the first intron of the C9ORF72 gene accounts for the majority of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) cases. Numerous studies have indicated the toxicity of dipeptide repeats (DPRs), which are produced via repeat-associated non-AUG (RAN) translation from the repeat expansion, and accumulate in the brain of C9FTD/ALS patients. Mouse models expressing the human C9ORF72 repeat and/or DPRs show variable pathological, functional and behavioral characteristics of FTD and ALS. Here, we report a new Tet-on inducible mouse model that expresses 36× pure G4C2 repeats with 100-bp upstream and downstream human flanking regions. Brain-specific expression causes the formation of sporadic sense DPRs aggregates upon 6 months of dox induction, but no apparent neurodegeneration. Expression in the rest of the body evokes abundant sense DPRs in multiple organs, leading to weight loss, neuromuscular junction disruption, myopathy and a locomotor phenotype within the time frame of 4 weeks. We did not observe any RNA foci or pTDP-43 pathology. Accumulation of DPRs and the myopathy phenotype could be prevented when 36× G4C2 repeat expression was stopped after 1 week. After 2 weeks of expression, the phenotype could not be reversed, even though DPR levels were reduced. In conclusion, expression of 36× pure G4C2 repeats including 100-bp human flanking regions is sufficient for RAN translation of sense DPRs, and evokes a functional locomotor phenotype. Our inducible mouse model suggests that early diagnosis and treatment are important for C9FTD/ALS patients. This article has an associated First Person interview with the first author of the paper.
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- 2021
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35. Efficient cache use for stencil operations on structured discretization grids
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Frumkin, Michael A. and Van der Wijngaart, Rob F.
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Computer Science - Performance ,Computer Science - Computational Complexity ,C.4 ,B.8 - Abstract
We derive tight bounds on cache misses for evaluation of explicit stencil operators on structured grids. Our lower bound is based on the isoperimetrical property of the discrete octahedron. Our upper bound is based on good surface to volume ratio of a parallelepiped spanned by a reduced basis of the inter- ference lattice of a grid. Measurements show that our algorithm typically reduces the number of cache misses by factor of three relative to a compiler optimized code. We show that stencil calculations on grids whose interference lattice have a short vector feature abnormally high numbers of cache misses. We call such grids unfavorable and suggest to avoid these in computations by appropriate padding. By direct measurements on MIPS R10000 we show a good correlation of abnormally high cache misses and unfavorable three-dimensional grids., Comment: tex .tar.gz file, including ps file, 16 pagest, 5 figures, 2 Appendicies
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- 2000
36. Lack of a Clear Behavioral Phenotype in an Inducible FXTAS Mouse Model Despite the Presence of Neuronal FMRpolyG-Positive Aggregates
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Saif N. Haify, Ruchira S. D. Mankoe, Valerie Boumeester, Esmay C. van der Toorn, Rob F. M. Verhagen, Rob Willemsen, Renate K. Hukema, and Laurens W. J. Bosman
- Subjects
FXTAS ,nuclear inclusions ,mouse behavior ,FMR1 ,repeat expansion ,Biology (General) ,QH301-705.5 - Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a rare neurodegenerative disorder caused by a 55–200 CGG repeat expansion in the 5′ untranslated region of the Fragile X Mental Retardation 1 (FMR1) gene. FXTAS is characterized by progressive cerebellar ataxia, Parkinsonism, intention tremors and cognitive decline. The main neuropathological hallmark of FXTAS is the presence of ubiquitin-positive intranuclear inclusions in neurons and astrocytes throughout the brain. The molecular pathology of FXTAS involves the presence of 2 to 8-fold elevated levels of FMR1 mRNA, and of a repeat-associated non-AUG (RAN) translated polyglycine peptide (FMRpolyG). Increased levels of FMR1 mRNA containing an expanded CGG repeat can result in cellular toxicity by an RNA gain-of-function mechanism. The increased levels of CGG repeat-expanded FMR1 transcripts may create RNA foci that sequester important cellular proteins, including RNA-binding proteins and FMRpolyG, in intranuclear inclusions. To date, it is unclear whether the FMRpolyG-positive intranuclear inclusions are a cause or a consequence of FXTAS disease pathology. In this report we studied the relation between the presence of neuronal intranuclear inclusions and behavioral deficits using an inducible mouse model for FXTAS. Neuronal intranuclear inclusions were observed 4 weeks after dox-induction. After 12 weeks, high numbers of FMRpolyG-positive intranuclear inclusions could be detected in the hippocampus and striatum, but no clear signs of behavioral deficits related to these specific brain regions were found. In conclusion, the observations in our inducible mouse model for FXTAS suggest a lack of correlation between the presence of intranuclear FMRpolyG-positive aggregates in brain regions and specific behavioral phenotypes.
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- 2020
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37. Safety and efficacy of RFA versus MWA for T1a renal cell carcinoma
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Brigit M. Aarts, Fernando M. Gomez, Marta Lopez-Yurda, Rob F. M. Bevers, Joris Herndriks, Regina G. H. Beets-Tan, Axel Bex, Elisabeth G. Klompenhouwer, Rutger W. van der Meer, Beeldvorming, RS: GROW - R3 - Innovative Cancer Diagnostics & Therapy, and Faculteit FHML Centraal
- Subjects
Propensity score ,Radiology, Nuclear Medicine and imaging ,General Medicine ,interventional ,Ablation ,Radiology ,Renal cell carcinoma ,neoplasm - Abstract
Objectives Percutaneous radiofrequency ablation (RFA) is stated as a treatment option for renal cell carcinoma (RCC) smaller than 4 cm (T1a). Microwave ablation (MWA) is a newer technique and is still considered experimental in some guidelines. The objective of this study was to compare the safety and efficacy of RFA and MWA for the treatment of RCC. Methods Patients with T1a RCC treated by RFA or MWA in two referral centers were retrospectively analyzed. Patient records were evaluated to generate mRENAL nephrometry scores. Local tumor progression (LTP) was considered when new (recurrence) or residual tumor enhancement within/adjacent to the ablation zone was objectified. Differences in LTP-free interval (residual + recurrence) between ablation techniques were assessed with Cox proportional hazards models and propensity score (PS) methods. Results In 164 patients, 87 RFAs and 101 MWAs were performed for 188 RCCs. The primary efficacy rate was 92% (80/87) for RFA and 91% (92/101) for MWA. Sixteen patients had residual disease (RFA (n = 7), MWA (n = 9)) and 9 patients developed recurrence (RFA (n = 7), MWA (n = 2)). LTP-free interval was significantly worse for higher mRENAL nephrometry scores. No difference in LTP-free interval was found between RFA and MWA in a model with inverse probability weighting using PS (HR = 0.99, 95% CI 0.35–2.81, p = 0.98) and in a PS-matched dataset with 110 observations (HR = 0.82, 95% CI 0.16–4.31, p = 0.82). Twenty-eight (14.9%) complications (Clavien-Dindo grade I–IVa) occurred (RFA n = 14, MWA n = 14). Conclusion Primary efficacy for ablation of RCC is high for both RFA and MWA. No differences in efficacy and safety were observed between RFA and MWA. Key Points • Both RFA and MWA are safe and effective ablation techniques in the treatment of T1a renal cell carcinomas. • High modified RENAL nephrometry scores are associated with shorter local tumor progression-free interval. • MWA can be used as heat-based ablation technique comparable to RFA for the treatment of T1a renal cell carcinomas.
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- 2023
38. How do HRD professionals and business managers interact in organizing HRD activities?
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Henriette Lundgren, Rob F. Poell, and Department of Human Resource Studies
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WORK ,Organizational Behavior and Human Resource Management ,ORGANIZATIONS ,DEVOLUTION ,STRUCTURATION THEORY ,LINE ,DEVOLVEMENT ,Arts and Humanities (miscellaneous) ,PEOPLE MANAGEMENT ,actor theory ,organizing HRD activities ,PERSPECTIVE ,interaction with business managers ,structure theory ,HUMAN-RESOURCE DEVELOPMENT - Abstract
Human resource development (HRD) has traditionally been seen as the main driver behind people-centered developmental activities such as learning and development, organization development, and career development. However, the role of HRD professionals as the main stakeholder has been questioned as more and more people-centered development activities have been integrated into a broad range of leadership and supervisory roles within the organization. The question arises: How do HRD professionals and business managers interact in organizing HRD activities? Building on structure and actor theories as a theoretical foundation, the study combines deductive and inductive data analysis of semi-structured interviews to review the roles of HRD professionals and business managers involved in organizing HRD activities in six different organizations in the USA. Our findings show that while training does not appear in any of the HR-related job titles, the term “training” is more common in business managers' titles describing their link to HRD activities. When organizing those activities, HRD professionals and business managers engage extensively in emergent partnering structures. While some HRD professionals are the main actors in some learning networks, business managers drive HRD activities in others. We discuss the commingling of actors and its impact on the learning network. The paper closes with a discussion of research limitations, future research, and implications for HRD practice.
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- 2023
39. Personality Testing and Workplace Training: Exploring Stakeholders, Products and Purpose in Western Europe
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Lundgren, Henriette, Kroon, Brigitte, and Poell, Rob F.
- Abstract
Purpose: The purpose of this paper is to explore how and why personality tests are used in workplace training. This research paper is guided by three research questions that inquire about the role of external and internal stakeholders, the value of psychometric and practical considerations in test selection, and the purpose of personality test use in workplace training. Design/methodology/approach: This research paper uses multiple-case study analysis. Interviews, test reports, product flyers and email correspondence were collected and analyzed from publishers, associations, psychologists and human resource development (HRD) practitioners in Germany, the UK and The Netherlands between 2012 and 2016. Findings: Themes emerge around industry tensions among practitioners and professional associations, psychologists and non-psychologists. Ease of use is a more important factor than psychometrics in the decision-making process. Also, practitioners welcome publishers that offer free coaching support. In the process of using tests for development rather than assessment, re-labeling takes place when practitioners and publishers use positive terms for personality tests as tools for personal stocktaking and development. Research limitations/implications: Despite extensive data collection and analysis efforts, this study is limited by its focus on a relatively small number of country cases and stakeholders per case. Practical implications: By combining scientific evidence with practical application, stakeholders can take first steps toward more evidence-based HRD practice around personality testing in workplace training. Originality/value: Little academic literature exists on the use of personality testing in workplace training. Without a clear understanding of the use of personality testing outside personnel selection, the current practice of personality tests for developmental purposes could raise ethical concerns about the rights and responsibilities of test takers.
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- 2017
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40. Drainage van symptomatische lymfoceles na pelviene lymfeklierdissectie: een retrospectief overzicht met langdurige follow-up
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Bovelander, Elke, Brouwer, Oscar R., van Gennep, Erik J., Bevers, Rob F. M., and Buddingh, Tim
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- 2018
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41. Exploring Perspectives on Antimicrobial Use in Livestock: A Mixed-Methods Study of UK Pig Farmers
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Lucy A. Coyne, Sophia M. Latham, Susan Dawson, Ian J. Donald, Richard B. Pearson, Rob F. Smith, Nicola J. Williams, and Gina L. Pinchbeck
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antimicrobial resistance ,antimicrobial ,antibiotic ,antimicrobial use ,farm animal ,behavior ,Veterinary medicine ,SF600-1100 - Abstract
Increasing levels of antimicrobial resistance in human and veterinary medicine have raised concerns over the irresponsible use of antimicrobials. The role of administering antimicrobials in food producing animals most frequently falls to the farmer, therefore it is essential that their use of antimicrobials is both optimal and responsible. This study sought in-depth information on the drivers behind antimicrobial use behaviors and farmer attitudes to responsible use using a mixed-methodological approach. Initially, in-depth semi-structured interviews were conducted with a purposively selected sample of farmers (n = 22). A thematic analysis approach was taken to identify key themes from these qualitative data. The generalizability and variation of these themes was then tested on a larger randomly selected sample of pig farmers through a questionnaire study (n = 261). The influences behind antimicrobial use were complex with multiple drivers motivating decisions. There was no consensual opinion on what farming systems resulted in either a low or high antimicrobial requirement however, farmers reported that good management practices, low stocking densities, and a high health status were associated with low antimicrobial use. Farmers expressed desire to avoid the long-term use of in-feed antimicrobials, but identified barriers to discontinuing such behaviors, such as pig morbidity, mortality, and economic losses. The high cost of antimicrobials was described as a motivation toward seeking alternative methods of controlling disease to prophylactic use; however, this expense was balanced against the losses from an increased burden of disease. The high financial costs involved in pig production alongside the economic uncertainty of production and pressure from retailers, were identified as limiting the scope for improvements in pig accommodation and facilities which could reduce the antimicrobial requirements on farm. Long-term, sustainable and economically stable relationships between retailers and farmers may allow farmers to make necessary investments in improving management and housing in order to reduce antimicrobial use. Greater use and more widespread deployment of effective vaccinations were highlighted by farmers as being a feasible alternative to antimicrobial use in preventing disease.
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- 2019
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42. Solving inverse scattering problems via reduced-order model embedding procedures
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Zimmerling, Jörn, Druskin, Vladimir, Guddati, Murthy N, Cherkaev, Elena, Remis, Rob F, Zimmerling, Jörn, Druskin, Vladimir, Guddati, Murthy N, Cherkaev, Elena, and Remis, Rob F
- Abstract
We present a reduced-order model (ROM) methodology for inverse scattering problems in which the ROMs are data-driven, i.e. they are constructed directly from data gathered by sensors. Moreover, the entries of the ROM contain loc- alised information about the coefficients of the wave equation. We solve the inverse problem by embedding the ROM in physical space. Such an approach is also followed in the theory of ‘optimal grids,’ where the ROMs are interpreted as two-point finite-difference discretisations of an underlying set of equations of a first-order continuous system on this special grid. Here, we extend this line of work to wave equations and introduce a new embedding technique, which we call Krein embedding, since it is inspired by Krein’s seminal work on vibrations of a string. In this embedding approach, an adaptive grid and a set of medium parameters can be directly extracted from a ROM and we show that several limitations of optimal grid embeddings can be avoided. Furthermore, we show how Krein embedding is connected to classical optimal grid embed- ding and that convergence results for optimal grids can be extended to this novel embedding approach. Finally, we also briefly discuss Krein embedding for open domains, that is, semi-infinite domains that extend to infinity in one direction., eSSENCE - An eScience Collaboration
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- 2023
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43. miRNA Expression Analysis of the Hippocampus in a Vervet Monkey Model of Fetal Alcohol Spectrum Disorder Reveals a Potential Role in Global mRNA Downregulation
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Gillis, Rob F., primary and Palmour, Roberta M., additional
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- 2023
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44. Temozolomide and Lomustine Induce Tissue Factor Expression and Procoagulant Activity in Glioblastoma Cells In Vitro
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Kapteijn, Maaike Y., primary, Zwaan, Shanna, additional, ter Linden, Esther, additional, Laghmani, El Houari, additional, van den Akker, Rob F. P., additional, Rondon, Araci M. R., additional, van der Zanden, Sabina Y., additional, Neefjes, Jacques, additional, Versteeg, Henri H., additional, and Buijs, Jeroen T., additional
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- 2023
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45. An integrated target field framework for point-of-care halbach array low-field MRI system design
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Bart de Vos, Rob F. Remis, and Andrew G. Webb
- Subjects
Radiological and Ultrasound Technology ,Gradient coil ,Halbach array ,Inverse source problem ,RF coil ,Biophysics ,Radiology, Nuclear Medicine and imaging ,Low-Field MRI ,System Design - Abstract
Objective Low-cost low-field point-of-care MRI systems are used in many different applications. System design has correspondingly different requirements in terms of imaging field-of-view, spatial resolution and magnetic field strength. In this work an iterative framework has been created to design a cylindrical Halbach-based magnet along with integrated gradient and RF coils that most efficiently fulfil a set of user-specified imaging requirements. Methods For efficient integration, target field methods are used for each of the main hardware components. These have not been used previously in magnet design, and a new mathematical model was derived accordingly. These methods result in a framework which can design an entire low-field MRI system within minutes using standard computing hardware. Results Two distinct point-of-care systems are designed using the described framework, one for neuroimaging and the other for extremity imaging. Input parameters are taken from literature and the resulting systems are discussed in detail. Discussion The framework allows the designer to optimize the different hardware components with respect to the desired imaging parameters taking into account the interdependencies between these components and thus give insight into the influence of the design choices.
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- 2023
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46. Temozolomide and Lomustine Induce Tissue Factor Expression and Procoagulant Activity in Glioblastoma Cells In Vitro
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Maaike Y. Kapteijn, Shanna Zwaan, Esther ter Linden, El Houari Laghmani, Rob F. P. van den Akker, Araci M. R. Rondon, Sabina Y. van der Zanden, Jacques Neefjes, Henri H. Versteeg, and Jeroen T. Buijs
- Subjects
Cancer Research ,Oncology ,cancer-associated thrombosis ,venous thromboembolism ,glioblastoma ,chemotherapy ,tissue factor ,extracellular vesicles ,temozolomide ,lomustine - Abstract
Glioblastoma (GBM) patients have one of the highest risks of venous thromboembolism (VTE), which is even further increased upon treatment with chemotherapy. Tissue factor (TF) is the initiator of the extrinsic coagulation pathway and expressed by GBM cells. In this study, we aimed to examine the effect of routinely used chemotherapeutic agents Temozolomide (TMZ) and Lomustine (LOM) on TF procoagulant activity and expression in GBM cells in vitro. Three human GBM cell lines (U-251, U-87, U-118) were exposed to 100 µM TMZ or 30 µM LOM for 72 h. TF procoagulant activity was assessed via an FXa generation assay and TF gene and protein expression through qPCR and Western blotting. The externalization of phosphatidylserine (PS) was studied using Annexin V flow cytometry. Treatment with TMZ and LOM resulted in increased procoagulant activity in all cell lines. Furthermore, both agents induced procoagulant activity in the supernatant and tumor-cell-secreted extracellular vesicles. In line, TF gene and protein expression were increased upon TMZ and LOM treatment. Additionally, PS externalization and induction of inflammatory-associated genes were observed. Overall, the chemotherapeutic modalities TMZ and LOM induced procoagulant activity and increased TF gene and protein expression in all GBM cell lines tested, which may contribute to the increased VTE risk observed in GBM patients undergoing chemotherapy.
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- 2023
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47. Meaningful work and resilience among teachers: The mediating role of work engagement and job crafting.
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Jessica Van Wingerden and Rob F Poell
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Medicine ,Science - Abstract
Research in the field of work and organizational psychology more and more highlights the importance of employees' experience of meaningful work. Adding to this area of research, the present study among teachers examined the relationship between meaningful work and resilience and tested whether this proposed relationship is mediated by teachers' work engagement and job crafting behaviour. Data for this study was collected among a group of Dutch teachers working in a school for primary education (N = 174). To test the hypothesized relationships, we conducted a bootstrapping analysis. The outcomes revealed that work engagement and job crafting fully mediated the relationship between meaningful work and teacher's resilience. The insights provided in this study may be useful for the deliberate cultivation of teachers' resilience and may help them to stay enthusiastic in their meaningful but demanding profession. Theoretical contributions, limitations, suggestions for future research and practical implications are discussed.
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- 2019
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48. Are we restoring functional fens? - The outcomes of restoration projects in fens re-analysed with plant functional traits.
- Author
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Agata Klimkowska, Klara Goldstein, Tomasz Wyszomirski, Łukasz Kozub, Mateusz Wilk, Camiel Aggenbach, Jan P Bakker, Heinrich Belting, Boudewijn Beltman, Volker Blüml, Yzaak De Vries, Beate Geiger-Udod, Ab P Grootjans, Petter Hedberg, Henk J Jager, Dick Kerkhof, Johannes Kollmann, Paweł Pawlikowski, Elisabeth Pleyl, Warner Reinink, Hakan Rydin, Joachim Schrautzer, Jan Sliva, Robert Stańko, Sebastian Sundberg, Tiemo Timmermann, Lesław Wołejko, Rob F van der Burg, Dick van der Hoek, Jose M H van Diggelen, Adrie van Heerden, Loekie van Tweel, Kees Vegelin, and Wiktor Kotowski
- Subjects
Medicine ,Science - Abstract
In peatland restoration we often lack an information whether re-established ecosystems are functionally similar to non-degraded ones. We re-analysed the long-term outcomes of restoration on vegetation and plant functional traits in 38 European fens restored by rewetting (18 sites) and topsoil removal (20 sites). We used traits related to nutrient acquisition strategies, competitiveness, seed traits, and used single- and multi-trait metrics. A separate set of vegetation records from near-natural fens with diverse plant communities was used to generate reference values to aid the comparisons. We found that both restoration methods enhanced the similarity of species composition to non-degraded systems but trait analysis revealed differences between the two approaches. Traits linked to nutrient acquisition strategies indicated that topsoil removal was more effective than rewetting. After topsoil removal competitive species in plant communities had decreased, while stress-tolerant species had increased. A substantial reduction in nutrient availability ruled out the effect of initial disturbance. An ability to survive and grow in anoxic conditions was enhanced after restoration, but the reference values were not achieved. Rewetting was more effective than topsoil removal in restricting variation in traits values permitted in re-developing vegetation. We found no indication of a shift towards reference in seed traits, which suggested that dispersal constraint and colonization deficit can be a widespread phenomena. Two functional diversity indices: functional richness and functional dispersion showed response to restoration and shifted values towards reference mires and away from the degraded systems. We concluded that targeting only one type of environmental stressor does not lead to a recovery of fens, as it provides insufficient level of stress to restore a functional ecosystem. In general, restoration efforts do not ensure the re-establishment and long-term persistence of fens. Restoration efforts result in recovery of fen ecosystems, confirmed with our functional trait analysis, although more rigid actions are needed for restoring fully functional mires, by achieving high and constant levels of anoxia and nutrient stresses.
- Published
- 2019
- Full Text
- View/download PDF
49. Personalized local <scp>SAR</scp> prediction for parallel transmit neuroimaging at <scp>7T</scp> from a single <scp>T1</scp> ‐weighted dataset
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Wyger M. Brink, Sahar Yousefi, Prernna Bhatnagar, Rob F. Remis, Marius Staring, and Andrew G. Webb
- Subjects
Phantoms, Imaging ,body models ,deep learning ,Neuroimaging ,Radiology, Nuclear Medicine and imaging ,Neural Networks, Computer ,Magnetic Resonance Imaging ,subject-specific ,PTx ,SAR - Abstract
Purpose: Parallel RF transmission (PTx) is one of the key technologies enabling high quality imaging at ultra-high fields (≥7T). Compliance with regulatory limits on the local specific absorption rate (SAR) typically involves over-conservative safety margins to account for intersubject variability, which negatively affect the utilization of ultra-high field MR. In this work, we present a method to generate a subject-specific body model from a single T1-weighted dataset for personalized local SAR prediction in PTx neuroimaging at 7T. Methods: Multi-contrast data were acquired at 7T (N = 10) to establish ground truth segmentations in eight tissue types. A 2.5D convolutional neural network was trained using the T1-weighted data as input in a leave-one-out cross-validation study. The segmentation accuracy was evaluated through local SAR simulations in a quadrature birdcage as well as a PTx coil model. Results: The network-generated segmentations reached Dice coefficients of 86.7% ± 6.7% (mean ± SD) and showed to successfully address the severe intensity bias and contrast variations typical to 7T. Errors in peak local SAR obtained were below 3.0% in the quadrature birdcage. Results obtained in the PTx configuration indicated that a safety margin of 6.3% ensures conservative local SAR estimates in 95% of the random RF shims, compared to an average overestimation of 34% in the generic “one-size-fits-all” approach. Conclusion: A subject-specific body model can be automatically generated from a single T1-weighted dataset by means of deep learning, providing the necessary inputs for accurate and personalized local SAR predictions in PTx neuroimaging at 7T.
- Published
- 2022
- Full Text
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50. Inclusive human resource management in freelancers' employment relationships: The role of organizational needs and freelancers' psychological contracts
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Sjanne Marie E. van den Groenendaal, Charissa Freese, Rob F. Poell, Dorien T. A. M. Kooij, and Department of Human Resource Studies
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WORK ,BREACH ,OUTCOMES ,dyad study ,Organizational Behavior and Human Resource Management ,freelancers ,IMPACT ,inclusive HRM ,organizational needs ,ATTITUDES ,employment relationship ,FIELD ,psychological contract ,HRM - Abstract
This study aimed to advance our understanding of inclusive human resource management (HRM) in freelance employment. We examined organizational needs and freelancers' psychological contracts with a qualitative interview study among eight dyads of HR managers and freelancers. Although the findings showed that organisations and freelancers have different interests, both parties agreed on what inclusive HRM entails in freelancers' employment relationships. However, within the dyads, the content of the psychological contract was not always viewed the same by HR managers and freelancers. Hence, negotiating mutual expectations when implementing inclusive HRM to avoid psychological contract breach appeared important. Furthermore, organizational needs did not seem to be considered when designing inclusive HRM. Due to this lack of strategic fit, organisations may waste opportunities of tapping into the full potential of hiring freelancers. The findings provide organisations insight in considering freelancers as potential sources of competitive advantage.
- Published
- 2022
- Full Text
- View/download PDF
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