High spatial resolution monolithic pixel detector in SOI technology Bugiel, R.; Bugiel, S.; Dannheim, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2021, Volume:
988
Journal Article
Peer reviewed
Open access
This paper presents test-beam results of monolithic pixel detector prototypes fabricated in 200 nm Silicon-On-Insulator (SOI) CMOS technology studied in the context of high spatial resolution ...performance. The tested detectors were fabricated on a 500 μm thick high-resistivity Floating Zone type n (FZ-n) wafer and on a 300 μm Double SOI Czochralski type p (DSOI Cz-p) wafer. The pixel size is 30 μm×30 μm and two different front-end electronics architectures were tested, a source follower and a charge-sensitive preamplifier. The test-beam data analyses were focused mainly on determination of the spatial resolution and the hit detection efficiency. In this work different cluster formation and position reconstruction methods are studied. In particular, a generalization of the standard η-correction adapted for arbitrary cluster sizes, is introduced. The obtained results give in the best case a spatial resolution of about 1.5 μm for the FZ-n wafer and about 3.0 μm for the DSOI Cz-p wafer, both detectors showing detection efficiency above 99.5%.
Flooding events can inflict major disruption on society and cause significant infrastructural and environmental damage. However, the adverse health impacts of flooding, particularly as they pertain ...to private groundwater resources used for consumption, are frequently overlooked. Whilst the literature has previously found a lack of well stewardship among private well owners under ‘normal’ conditions, our understanding of private well owners’ perceptions of and preparedness for the risks posed by flooding to their domestic well-water supply is limited. This study advances the qualitative literature on this subject. It is amongst the first qualitative studies employing focus groups to examine private well owners, and the first in an Irish context. Six focus groups were conducted in four counties in Ireland, with the themes emerging from the focus groups refined, organised, and interpreted in the context of the Health Belief Model. Most focus group participants expressed awareness of the potential severity of well contamination following flooding, but many did not consider their local area “at risk” of it, notwithstanding the occurrence of previous local flooding events. All focus group participants shared the view that owners were primarily responsible for their own wells. However, their capacity to undertake appropriate actions was reduced by reliance on visual and olfactory evidence to assess water quality, and concerns regarding the financial cost and accessibility of water testing facilities. The phenomenon of misperception was also evident among participants. In light of the increasing frequency and severity of extreme weather events including flooding, these findings provide direction for future socio-hydrogeological interventions. Targeted communication strategies highlighting the risks posed by flooding, mitigation measures that promote well stewardship, and protective behaviours are required. The provision of access to free well water testing would also promote protective actions.
Risk communication represents the optimal instrument for decreasing the incidence of private groundwater contamination and associated waterborne illnesses. However, despite attempts to promote ...voluntary well maintenance in high groundwater-reliant regions such as the Republic of Ireland, awareness levels of supply status (e.g. structural integrity) have remained low. As investigations of supply awareness are often thematically narrow and homogeneous with respect to sub-population, revised analyses of awareness among both current and future supply owners (i.e. adults of typical well owner and student age) are necessary. Accordingly, the current study utilised a national survey of well users and an age-based comparison of supply awareness. Awareness was measured among 560 Irish private well users using a multi-domain scoring framework and analysed in conjunction with experiential variables including experience of extreme weather events and previous household infections, and perceived self-efficacy in maintaining supply. Respondents displayed a median overall awareness score of 66.7%, with supply owners (n = 399) and students (n = 161) exhibiting median scores of 75% and 58.3%. Awareness among both combined respondent subsets and well owners was significantly related to gender, well use factors and self-perceived behavioural efficacy while awareness among students was not correlated with any independent variable. Cluster analysis identified three distinct respondent groups characterised by awareness score and gender in both current and future well owner subsets. Male well owners and students displayed higher perceived self-efficacy irrespective of awareness score while female well owners that demonstrated high awareness were significantly more likely to report postgraduate educational (p < 0.001). Findings suggest that recent experience of extreme weather events does not significantly influence supply awareness and mirror previously identified knowledge differences between well owners and young adults. Age, gender, supply use and perceived self-efficacy emerge as recurring focal points and accordingly merit consideration from groundwater and health communication practitioners for future risk interventions.
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•Awareness of private well management factors quantified among 560 Irish well users•Awareness scores compared between two age-related subsets.•Median awareness score was 66.7%, with well owners markedly outperforming students.•Awareness- and gender-based clusters identified in each subset.•Socio-demographics, perceived self-efficacy and well use recurring determinants of awareness.
Extreme weather events (EWEs) may significantly increase pathogenic contamination of private (unregulated) groundwater supplies. However, due to the paucity of protective guidance, private well users ...may be ill-equipped to undertake adaptive actions. With rising instances of waterborne illness documented in groundwater-dependent, developed regions such as the Republic of Ireland, a better understanding of well user risk perceptions pertaining to EWEs is required to establish appropriate educational interventions. To this end, the current study employed an online and physical questionnaire to identify current risk perceptions and correspondent predictors among Irish private well users concerning extreme weather. Respondents were elicited via purposive sampling, with 515 private well users elucidating perceived supply contamination risk in the wake of five EWEs between the years 2013–2018 including drought and pluvial flooding. A novel scoring protocol was devised to quantify overall risk perception (i.e. perceived likelihood, severity and consequences) of extreme weather impacts. Overall risk perception of EWEs was found to demonstrate a significant relationship with gender (p = 0.017) and event experience (p < 0.001), with female respondents and those reporting prior event experience exhibiting higher median risk perception scores. Risk perception was additionally mediated by perceived self-efficacy in undertaking supply maintenance (p = 0.001), as well users citing confidence in ability scored significantly lower than those citing no confidence. Two-step cluster analysis identified three distinct respondent subsets based on risk perception of EWEs (high, moderate and low perception), with female respondents and those with a third-level education significantly more likely to fall within the high perception cluster. Study findings affirm that certain demographic, experiential and cognitive factors exert a significant influence on private well user risk perceptions of EWE impacts and highlight potential focal points for future educational interventions seeking to reduce the risk of human infection associated with groundwater and extreme weather.
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•515 Irish private well users surveyed•Median overall risk perception score of 50% measured•Risk perception associated with several predictors including gender and climate change•Three distinct perception-based respondent clusters identified•Findings useful for climate change communication and intervention
Private well users in Ontario are responsible for protective actions, including source maintenance, treatment, and submitting samples for laboratory testing. However, low participation rates are ...reported, thus constituting a public health concern, as risk mitigation behaviours can directly reduce exposure to waterborne pathogens. The current study examined the combined effects of socio-demographic profile, experience(s), and “risk domains” (i.e., awareness, attitudes, risk perceptions and beliefs) on behaviours, and subsequently classified private well users in Ontario based on cognitive factors. A province-wide online survey (n = 1228) was employed to quantify Ontario well owners' awareness, perceptions, and behaviours in relation to their personal groundwater supply and local contamination sources. A scoring protocol for four risk domains was developed. Two-step cluster analysis was used to classify respondents based on individual risk domain scores. Logistic regression was employed to identify key variables associated with cluster membership (i.e., profile analysis). Overall, 1140 survey respondents were included for analyses. Three distinct clusters were identified based on two risk domains; groundwater awareness and source risk perception. Profile analyses indicate “low awareness and source risk perception” (Low A/SRP) members were more likely male, while “low awareness and moderate source risk perception” (Low A/Mod SRP) members were more likely female and bottled water users. Well users characterised as “high awareness and source risk perception” (High A/SRP) were more likely to report higher educational attainment and previous well water testing. Findings illustrate that socio-cognitive clusters and their components (i.e., demographics, awareness, attitudes, perceptions, experiences, and protective actions) are distinct based on the likelihood, frequency, and magnitude of waterborne pathogen exposures (i.e., risk-based). Risk-based clustering, when incorporated into quantitative microbial risk assessment, enables the development of effective risk management and communication initiatives that are demographically focused and tailored to specific sub-groups.
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•Cognitive factors (e.g., awareness, risk perception) quantified among 1140 well users.•Behaviours significantly associated with calculated awareness and risk perception.•Three sub-groups “socio-cognitive profiles” identified based on awareness and risk perception.•Socio-demographic, experience and behaviour significantly associated with profiles.•Profiles distinct based on frequency and magnitude of waterborne pathogen exposures
Consolidation of multi-domain risk management research is essential for strategies facilitating the concerted government (educational) and population-level (behavioural) actions required to reduce ...microbial private groundwater contamination. However, few studies to date have synthesised this literature or sought to ascertain the causal generality and extent of supply contamination and preventive responses. In light of the Republic of Ireland (ROI) and Ontario's high reliance and research focus on private wells and consequent utility for empirical comparison, a scoping review of pertinent literature (1990–2022) from both regions was undertaken. The SPICE (Setting, Perspective, Intervention, Comparison, Evaluation) method was employed to inform literature searches, with Scopus and Web of Science selected as primary databases for article identification. The review identified 65 relevant articles (Ontario = 34, ROI = 31), with those investigating well user actions (n = 22) and groundwater quality (n = 28) the most frequent. A markedly higher pooled proportion of private supplies in the ROI exhibited microbial contamination (38.3 % vs. 4.1 %), despite interregional similarities in contamination drivers (e.g., weather, physical supply characteristics). While Ontarian well users demonstrated higher rates of historical (≥ 1) and annual well testing (90.6 % vs. 71.1 %; 39.1 % vs. 8.6 %) and higher rates of historical well treatment (42.3 % vs. 24.3 %), interregional levels of general supply knowledge were analogous (70.7 % vs. 71.0 %). Financial cost, organoleptic properties and residence on property during supply construction emerged as predictors of cognition and behaviour in both regions. Review findings suggest broad interregional similarities in drivers of supply contamination and individual-level risk mitigation, indicating that divergence in contamination rates may be attributable to policy discrepancies – particularly well testing incentivisation. The paucity of identified intervention-oriented studies further highlights the importance of renewed research and policy agendas for improved, targeted well user outreach and incentivised, convenience-based services promoting routine supply maintenance.
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•Literature review considers private well contamination in Ontario and Ireland.•Of 65 relevant articles, 10 directly address risk communication and policy.•Pooled supply contamination rates in Ireland markedly higher than in Ontario.•Supply awareness levels similar, despite higher well maintenance rates in Ontario.•Review identifies interregional parallels and merit in incentive-based intervention.