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Delaying reward feedback does not increase the influence of information on attentional priority in visual search
No full textDemonstrations of information-seeking behaviour suggest that attention often acts in an exploitative way, prioritising stimuli that provide diagnostic information about upcoming events over stimuli associated with uncertainty. However, recent evidence from studies of attentional capture in visual search show an opposite pattern: automatic prioritisation of items associated with reward uncertainty over diagnostic stimuli. We hypothesise that this uncertainty-modulated attentional capture (UMAC) effect reflects ‘attention for learning’: that is, exploration of potential sources of new information. Here we investigated whether UMAC arises because immediate provision of reward feedback in prior studies rendered advance information redundant, attenuating exploitation of diagnostic items and promoting exploration. Accordingly, increasing the duration of anticipated uncertainty (and hence the value of advance information that allows us to escape uncertainty earlier) should promote prioritisation of diagnostic cues and lead to patterns of attentional exploitation. In two eye-tracking experiments, we compared attentional capture by a cue providing diagnostic reward information and a cue signalling uncertain reward, while manipulating the delay between response and feedback (i.e., the duration of anticipated uncertainty that advance information could forestall). We found a UMAC effect in all conditions: regardless of response–feedback delay, uncertain stimuli were more likely to capture attention than diagnostic stimuli. These results suggest that prioritisation of uncertainty is a robust pattern of behaviour in this task. Synthesising current and previous findings, we suggest that different modes of attentional information-seeking may reflect qualitative task differences, with exploration operating at an implicit, automatic level, and exploitation resulting from top-down, volitional processes.</p
Technical note: Movement-related artifacts in local field potential signals may influence adaptive deep brain stimulation
No full textRobot Social Skills: Influencing Children’s Performance and Robot Perception Through a Robot Math Tutor’s Scaffolding and Personalization
No full textTailoring Prostate Cancer Surgery:Radio- and fluorescence guidance to improve surgical accuracy
Full text linkThis thesis studied and confirmed that image-guided surgery in prostate cancer is an innovative way to operate with greater precision. First, a systematic review was conducted of what was known worldwide at that time. This was studied more in depth through a Delphi consensus proces with international panel members. The wishes and requirements of daily practicioners of targeted surgery were analyzed, and gave us insights in how to proceed in future research. To visualize anatomical structures, tracers can be used during surgery to identify, for example, the sentinel lymph node or the lymphatic pathways in their entirety from the prostate (and other organs). To remove the tumor-containing tissue while sparing healthy tissue, a tracer that specifically binds to the prostate-specific membrane antigen (PSMA) and is therefore selective for prostate cancer can be used. Both fluorescence and radio-guided surgery are options here. The focus of this thesis is on the advantages and disadvantages of fluorescence and radio-guided applications. The ultimate goal is to develop a prostate-specific tracer that is both fluorescent and radioactive (hybrid). The follow-up to this in the form of a “first-in-human” trial with the hybrid PSMA tracer is expected this year
Black Plastic Identification for Sorting and Recycling With Deep-UV Raman Spectroscopy
No full textWe present a deep-ultraviolet (DUV) Raman spectrometer for plastic identification for sorting purposes in a recycling facility. Plastic recycling entails processing large volumes of inhomogeneous plastic waste of different colors, sizes, and polymer types. Currently, hyperspectral imaging in the near-infrared is one of the leading techniques for plastic identification for sorting purposes, but it falls short for dark or black plastics due to strong absorption. Alternatively, Raman spectroscopy could be used; however, conventional Raman technology at visible wavelengths often suffers from a strong fluorescence background that overwhelms the Raman signal, hampering the identification of black plastics in particular. In contrast, Raman spectroscopy in the DUV wavelength range is suitable for black plastics because the fluorescence emission that occurs over the near-UV and visible range will not overlap with the Raman spectrum. Here, we present a dedicated DUV setup, based on a 248.6-nm NeCu laser and designed and tested for stand-off detection of black plastic waste objects on a conveyor belt. We characterized key parameters such as focal depth and detection at different conveyor speeds, emphasizing real-world applicability under recycling factory conditions. In this work, we focus on polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET), as these are considered commercially interesting. Analysis of the deep-UV spectra led to promising results for identification, for both stationary and moving conditions. We also demonstrate successful identification of multilayer materials (metalized or black coated) that are challenging for hyperspectral NIR techniques. We discuss advantages of this DUV Raman modality, options to overcome its current shortcomings, and its future potential for polyolefin sorting in a recycling factory.</p
The Economics and Econometrics of Gene–Environment Interplay
No full textWe discuss how to estimate the interplay between genes (nature) and environments (nurture), with an empirical illustration of the moderating effect of school starting age on one’s genetic predisposition towards educational attainment. We argue that gene–environment (G × E) studies can be instrumental for (i) assessing treatment effect heterogeneity, (ii) testing theoretical predictions, and (iii) uncovering mechanisms, thereby improving understanding of how (policy) interventions affect population subgroups. Empirically, we find that being old-for-grade and having a higher genetic propensity for education benefits children on assessment tests as they progress through school. In this setting, families appear to increase genetic inequalities while schools seem to reduce them.</p
A unique light-harvesting complex protein family, LHCE, is involved in far-red absorption by photosystems I and II in Euglena gracilis
No full textPhotosynthetic organisms have evolved diverse strategies to adapt to fluctuating light conditions, balancing efficient light capture with photoprotection. In green algae and land plants, this involves specialized light-harvesting complexes (LHCs), non-photochemical quenching, and state transitions driven by dynamic remodeling of antenna proteins associated with PSI and PSII. Euglena gracilis, a flagellate with a secondary green plastid, represents a distantly related lineage whose light-harvesting regulation remains poorly understood. Although spectral shifts under different light regimes have been observed, their molecular basis has been unknown. Here, through integrated phylogenomic, proteomic, structural, and spectroscopic analyses, we identify a novel chlorophyll a far-red-absorbing antenna complex in E. gracilis, composed of euglenozoa-specific Lhce proteins. This LHCE antenna complex forms a pentameric complex under low light and transiently associates with PSII during far-red light exposure. It is structurally and functionally distinct from canonical LHCII trimers and absent in Viridiplantae. Additionally, PSI in E. gracilis is surrounded by an expanded belt of Lhce and LhcbM proteins around a minimal core. These findings reveal a unique mechanism for regulating PS antenna size in E. gracilis that is distinct from known models in plants and green algae, and highlight an alternative evolutionary strategy for light acclimation in organisms with secondary plastids.</p
Referral to geriatric rehabilitation:Exploring triage
Full text linkSummary Older hospital patients are vulnerable to adverse outcomes of hospital stay. In aging societies, post-acute care (PAC) programs were developed to support functional recovery. This thesis focuses on the referral of older or frail hospital patients to geriatric rehabilitation (GR). GR consists of integrated, multidisciplinary care programs, targeted at older, vulnerable or multimorbid patients with acute functional decline. Across European countries the mean age of patients was 80 years . National GR-capacity and the duration of GR-stay varied greatly. Length of stay varied from 7 to 65 days. In 2013 geriatric rehabilitation was invested in the Netherlands with more than 50.000 GR trajectories each year. The eligibility for geriatric rehabilitation and triage, the decision making process concerning this referral is the subject of this thesis. Most patients are admitted to GR following a hospital stay. In Dutch hospitals, liaison nurses assess the eligibility of patients for GR and present candidates to GR-facilities. Admissions can be refused by the post-acute care facility for alleged absence of rehabilitation goals, patient complexity or medical instability. The outcome of hospital triage decisions can thus represent a source of tension between ‘sending’ and ‘receiving’ care settings, especially because responsibilities are not clear. Consensus in GR referral decision making, would support cooperation and allow for evaluation of GR patient flow, case mix and rehabilitation outcome. The triage instrument for geriatric rehabilitation developed in 2013 by the professional association of elderly care physicians, Verenso, mentions six conditions or patient-criteria to qualify for GR: 1.) vulnerability, 2.) rehabilitation needs, 3.) a positive functional prognosis 4.) learnability 5.) sufficient endurance to train and 6.) motivation . With the introduction of short-term recovery care (STRC, ‘Eerstelijnsverblijf’) in 2017 a decision aid was developed. The Verenso triage instrument nor the STRC decision aid has been evaluated. This thesis explored the evidence supporting a referral decision as well as the ‘triage assessment’ The research questions were: 1. What are older patients’ attitudes and thoughts regarding follow-up care at hospital discharge? A multi-method qualitative study, chapter 2. 2. What items, instruments and methods concerning referral of hospital patients to GR are reported in literature? A scoping review, chapter3. 3. What are the characteristics of hospital patients referred to GR in comparison with patients not referred? An observational cohort study, chapter4 4. Which hospital and/or rehabilitation professionals are involved in GR referral decision making and what triage items and methods are used? An observational cohort study, chapter 5. 5. What are core elements of a best practice referral to GR in the Netherlands? A national survey, chapter 6. These exploratory triage studies aimed to contribute to the quality of referral decision making by presenting a conceptual model of the multilevel triage process with its professional and organizational aspects. In the general discussion, the problem of GR-triage is depicted and the results of the triage studies as well as the limitations we encountered are reflected upon. Triage as a subject has characteristics of a ‘wicked problem’. Based on the results of the triage studies, elementary steps of a GR-triage process are described. Components are further depicted in three dimensions: 1) patient care; 2) professional competence; 3) organizational features. This conceptual triage model has not yet undergone a field consultation nor has it been evaluated in a wider context by stake holders, such as older patients, caregivers, residents, multidisciplinary GR teams, hospital and care facility managers, health insurance companies and policy makers. Implementation of the conceptual triage model could support the quality of decision making and facilitate evaluation of GR-triage practice. Implementation and evaluation underly a stepped process towards the development of a field standard
Managing Cybersecurity Risks of Human-Machine Interfaces (HMIS):an Adaptive Dynamical Systems Analysis
No full textAs industrial control systems become increasingly digitized, zero-day vulnerabilities in Human-Machine Interfaces (HMIs) pose critical threats to critical infrastructure, potentially enabling nation-state actors to cause physical damage while evading detection. This research analyses a significant gap in cyber risk management by developing a comprehensive modelling framework to understand how sophisticated cyber-physical attacks progress from initial compromise to catastrophic system failure. Using the Stuxnet worm as a foundational case study, this paper investigates how zero-day vulnerabilities in HMIs can be exploited to carry out advanced cyber-physical attacks. An adaptive network model is employed to simulate the progression of such an attack, from initial HMI compromise to physical system sabotage, while remaining undetected by operators. Crucial causal dependencies were identified, with their influence strengths and adaptive activation thresholds among the components modeled. A What-If analysis assesses how changes in system parameters affect the timing and likelihood of critical damage, incorporating probabilistic risk evaluation based on ISO 27005 standards. The findings provide actionable insights for cyber risk management professionals, enabling more effective threat assessment, improved network segmentation strategies, and enhanced detection capabilities for organizations operating critical infrastructure vulnerable to state-sponsored cyberattacks.</p
The Role of Demographic and Autism Specific Factors on the Level of Depression in Autistic Adults
No full textPURPOSE: Autistic adults often face co-occurring depressive symptoms. While previous studies have focused primarily on depression in children with autism, this study aims to investigate the factors associated with depressive syptoms in autistic adults. By examining a broader range of variables including sociodemographic factors and autistic traits like sensory sensitivity and restricted and repetitive behaviors, we seek to gain a more comprehensive understanding of the elevated levels of depression within this population.METHODS: This quantitative study utilized a cross-sectional design. Two hierarchical regression analyses were conducted. The first analysis included all participants (N=438), focusing on demographic factors such as age, gender, income, in the first model and autistic traits such as repetitive behaviors, and depressive symptoms in the second model. The second analysis included a reduced sample (N=305) that additionally incorporated sensory sensitivity data.RESULTS: Older age, lower income, and a greater number of co-occurring psychosocial problems were significantly associated with higher levels of depressive symptoms.CONCLUSIONS: Our research, unique by its large sample of adults with autism and innovative exploration of potential factors of influence, offers valuable insights into the unique challenges faced by autistic adults. Our findings highlight the difficulty older autistic individuals may encounter in accessing support services primarily designed for younger populations. Moreover, co-occurring problems and lower income can exacerbate these challenges, leading to instability and limited access to resources. These results underscore the urgent need for societal inclusion and tailored support systems to promote the mental well-being of autistic adults.</p