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The biofactory : implementing a life cycle sustainability assessment decision making tool for quantifying integral sustainability benefits of the wastewater circular economy in Chile.
(2023) Furness, Madeline
The “Biofactory” is a circular economy-based concept for wastewater treatment that improves
water quality, promotes efficient use of materials and energy, recovering resources, generating
stakeholder collaboration, and decreasing both emissions and costs. This proposes a solution for
the global challenge of integrated water and sanitation management. Due to socio-economic
bottlenecks, such as typical high costs and low public acceptance of novel resource recovery
scenarios in wastewater treatment, realizing the Biofactory goals becomes a difficult task. Decision
makers are currently unable to appreciate the environmental and social benefits of the Biofactory,
as most decision-making tools focus on mainly technical and economic aspects. This research is
the first to quantify integral sustainability benefits of co-product recovery of treated effluent,
biosolids, biogas and nutrient in two full-scale “Biofactory” wastewater circular economies in Chile.
Life Cycle Sustainability Assessment (LCSA) was implemented, combining Life Cycle Assessment
(LCA), Social Life Cycle Assessment (SLCA) and Life Cycle Costing (LCC) with a Multi-criteria
Decision Making (MCDM) model to quantify integral environmental, socio-cultural, and economic
sustainability impacts of two Plants, A and B. Three scenarios for each plant were considered,
discharge of wastewater without treatment, conventional wastewater treatment with no resource
recovery, and biofactory wastewater circular economy configurations, to determine if each plant
decrease impacts and determine which had better performance. LCA results showed Plant A
decreased overall environmental impact by -37 % compared to baseline conventional scenarios,
while Plant B -31 %. SLCA results showed Plant A decreased social impacts – 56 %, while Plant B
– 18 %, therefore, Plant A had better overall environmental and social performance. However, Plant
B decreased economic impacts by -48 % compared to an increase of 20 % in Plant A. Therefore,
when combining scores using a MCDM model, Plant A decreased total sustainability impacts
by -30 % and Plant B by -58 %, therefore, the resource recovery systems implemented in Plant B
had better overall sustainability performance. These results were discussed across process
contributions to environmental, social, and economic benefits. Model limitations were discussed,
and recommendations were made for future applications of this research. The investigation
demonstrated that the transition to WW-CEs improved integral sustainability according to the LCSAMCDM model implemented in both Plants. The urgent need to adopt sustainable decision-making
models was highlighted and discussed, to not only improve sanitation coverage, but also improve
sustainability performance of the sanitation industry across the globe.
Does a dimensionally-gated reselection process restrict the entry of visual features into working memory?
(2023) Williamson, Kieran James
Visual working memory (VWM) is a limited-capacity cognitive system that allows us to
maintain and manipulate visual information over a brief period of time. It plays a critical
role in many cognitive functions, including visual search, problem-solving, and decisionmaking. While the importance of VWM is not disputed, a critical issue addressed in
research is whether visual objects bind all their component features during VWM entry
or if task-relevant features are prioritised for representation. In a recent study,
Zhu et al. (2022) proposed that attended sensory information does not automatically
enter VWM, but instead is subject to an additional reselection process that determines
whether items are selected for VWM entry. Furthermore, they suggested that
reselection operates using a dimensional memory filter, such that when an individual
feature value (e.g., red) is selected for entry into VWM, all attended feature values
within the same feature dimension (e.g., all colours) automatically enter VWM. Across
three experiments, we systematically investigated these hypotheses by conceptually
replicating two of Zhu et al.’s experiments, while incorporating modifications to address
our concerns about their methodology. In Experiment 1, we investigated Zhu et al.’s
proposal that a reselection process operates to restrict the entry of features into VWM.
We assessed whether the irrelevant colour of a target object captured more attention
than a new colour when it appeared as a distractor singleton in an orthogonal visual
search task. We found that this was the case, indicating that the irrelevant colour of the
target object was held in VWM, contrary to the key result that Zhu et al. cited to support
reselection. In Experiments 2 and 3, we investigated Zhu et al.’s claim that VWM
consolidation operates via a dimensional memory filter. Specifically, we assessed
whether memorising the colour of a fixation cross would cause the task-irrelevant
colour of a target object to enter VWM. To determine whether this colour entered VWM,
we measured its interference in an orthogonal shape change detection task. Experiment
2 used a 700 ms ISI, while in Experiment 3, we reduced the ISI to 100 ms. Unlike Zhu et
al., who only reported trials where shape was consistent between displays, we included
trials where shape changed between displays in our analysis and included trials in
which the shape probe matched the memorised fixation colour. In Experiments 2 and 3,
we found evidence that the target colour had entered VWM, consistent with a
dimensional memory filter. However, we also found that the fixation colour had a
stronger impact on shape change detection than the target colour, a finding that was not
explicitly predicted by Zhu et al. Overall, our results align more closely with predictions
from object-file theory (Kahneman et al., 1992) and event-file theory (Hommel, 1998,
2004), which propose object-specific binding occurs during encoding, and objectspecific benefits and costs emerge during object retrieval and review. The facilitation
we observed when features were consistent between displays could reflect objectspecific repetition benefits, while the interference we observed when features partially
changed between displays may indicate partial repetition costs.
‘Akarongo, ‘Āpi‘i, Arataki Listen, Learn, Lead. Exploring the lived experiences and perspectives of Pacific peoples within climate change spaces : an Aotearoa context.
(2023) Timoteo, MahMah
Complex, nuanced, and devastating, the impacts of climate change are being felt on levels never experienced before in human history. Whilst many parts of the world are slowly, yet painfully becoming more exposed and familiar to the harmful and ever more destructive realities of the climate crisis, Pacific peoples and their communities have continued to be at the forefront of this global issue. Although much research has investigated the impact of climate change on Pacific Island nations, there is a lack of research that considers the multifaceted and intersectional lived experiences and voices of Pacific peoples and their navigation of the climate emergency, specifically within climate change spaces throughout Aotearoa New Zealand. This research aimed to explore the lived experiences of Pacific peoples in climate spaces within Aotearoa New Zealand and sought to identify the challenges Pacific peoples face whilst navigating these spaces. In doing so, this research sought to address such challenges by suggesting potential ways forward that can be implemented to aid the amplification and safety of Pacific peoples and their communities.
An intersectional postcolonial approach was employed which provided a lens in which systemic and institutional oppression, marginalisation, and discrimination could be identified and understood. It is through the analysis of power dynamics and roles within climate spaces and discussions that we revealed the significance of decentring whiteness, dismantling of Eurocentrism, and colonial domination within such climate spaces. The following research involved ten Pacific participants throughout Aotearoa New Zealand. Guiding the research was the implementation of the Cook Island ‘Tivaevae Methodology’. The ‘akaruru (data collection) method carried out was an interweaving of semi-structured interviews, participant-observations, and talanoa. Stitched throughout the key stages of Tivaevae were five core values of the tivaevae model: taokotai (collaboration), tu akangateitei (respect), uriuri kite (reciprocity), tu inangaro (relationships), and akairi kite (shared vision). These values laid the foundation for how this research was carried out, centering the prosperity and wellbeing of those involved in this research and nurturing the vā between us.
The key findings indicated that Pacific peoples and their community’s experiences of climate change spaces and discussions within Aotearoa New Zealand are dynamic, multifaceted, and complex. The talanoa sessions revealed that some Pacific peoples face various forms of discrimination and challenges within these spaces, with varying degrees of hardships brought about by oppressive systems and institutions upheld within Aotearoa New Zealand, which in turn negatively impacts their current livelihoods and futures. Informed by the lived experiences and perspectives shared by the participants involved, this research emphasises the imperative need for Pacific voices to be centred and amplified within climate change spaces and discussion. Furthermore, possible ways forward involve the decolonisation and indigenisation of systems and institutions that directly influence and impact climate spaces and beyond. Ways forward must be led by Pacific people and their communities to ensure the protection of their mana, safety, and future generations.
Freedom from exposure to intimate partner violence in early childhood and emotional regulation during middle childhood, among pacific childhood growing up in Aotearoa/New Zealand.
(2023) Hakeemi, Humaira
Background: Studies have consistently demonstrated that children exposed to
intimate partner violence (IPV) are at a higher risk of experiencing behavioural, physical, and
emotional problems. Recent findings from a longitudinal study revealed that within the
Pacific Islands Families (PIF) cohort, 41% of mothers identified themselves as either victims
or perpetrators of IPV, highlighting the prevalence of such violence in the lives of children.
Emotional regulation plays a critical in a child's development and well-being, emphasising
the importance of investigating early childhood experiences to understand the factors that
shape emotional health and identify protective measures. This study significantly contributes
to a deeper understanding of the unique needs and experiences of Pacific children, thereby
facilitating the development of targeted interventions tailored to this specific population.
Given that PIF communities often contend higher rates of IPV compared to other
demographic groups, this study aims to illuminate the distinct challenges they confront.
Research Aim: The purpose of this study was to examine the relationship between
freedom from exposure to IPV during early childhood (2-years) and emotional regulation
during middle childhood (9-years), among Pacific children growing up in Aotearoa/New
Zealand.
Methods: This study utilized the PIF study, a longitudinal birth cohort study
providing comprehensive data on the development of Pacific children in New Zealand. The
study’s participants consisted of Pacific infants born at Middlemore Hospital in Auckland
between March 15 to December 17, 2000. A total of participants completed both the IPV
questionnaire and the internalising problems questionnaire. IPV exposure in children was
assessed using mothers' reports at the 2-year measurement wave, while internalising
problems were evaluated based on reports from mothers, teachers, and children at the 9-
year measurement wave. Additionally, the study examined a child's report at the 9-year
measurement wave to explore potential factors, such as substance exposure and bullying, in
the relationship between IPV exposure and internalising problems.
Result: While the study did not find a direct association between mother-reported
IPV exposure and subsequent internalising problems, it did yield several significant findings.
Children self-reported significantly higher rates of internalising problems than anticipated,
with the severity of violence exposure notably impacting these rates. Specifically, children
who reported symptoms were 2.2 times more prevalent among those whose mothers reported
severe violence. Furthermore, mothers reported higher rates of internalising problems
compared to children in a US-based standardization sample. This study also identified that
children who had experienced bullying were at a 1.45 times increased risk of internalising
problems, a pattern consistently reported by the children themselves. Additionally, the
findings from this study indicated that children with access to any form of substance were
found to be at a 3.27 times higher risk for internalising problems when compared to children
without substance use. Despite the sample’s diversity, this study did not reveal any influences
of cultural orientation on the relationships between preschool physical IPV exposure and
middle childhood internalising problems.
Implication: It is important to interpret these results within the existing literature and
acknowledge the study’s limitations. The recruitment strategy used in the PIF study may
restrict the generalizability of the results, given that the study’s participants were restricted to
infants born at Middlemore Hospital and within the PIF study regions. It is possible that
individuals from other regions in New Zealand may experience internalising problems
differently. The relatively small sample size of 623 participants in this study could also affect
the generalizability of the results, potentially yielded different outcomes with a larger sample.
Previous research has produced varied results concerning the association between IPV
exposure and children’s internalising problems, with some studies demonstrating significant
associations and others showing no significant effects. This complexity underscores the
necessity for further investigation to gain a more profound understanding of the underlying
mechanisms and potential moderating factors involved.
Response biases in visual processing: the effect of similarity and attention on judgments of sameness.
(2023) Humphries, Ailsa M.
It is well known that humans exhibit biased behaviours. Research suggests that both
perceptual and cognitive biases arise from adaptive solutions to situations in which decisions
must be made in the absence of complete information. These biases result from the operation
of heuristics, or mental shortcuts, that evolved to keep us safe; to orient us towards friend and
away from foe. While some biases are considered negative, leading to prejudice and
discrimination, many are not; they are simply interesting tendencies that are worth studying to
better understand information processing. Research in visual comparison tasks has identified
two key biases. The spatial congruency bias (SCB) is a relative bias, with a greater tendency
to judge objects as “same” if they are presented at the same location compared with a different
location; and the overall bias (OB) is the average bias across all trials, that varies with overall
display similarity and the degree to which analytic processing is required. Studying these biases
will help with understanding the visual processing mechanisms that underlie object
comparison, a fundamental task in our everyday activities.
In two studies, signal detection theory was used to measure response bias and calculate
the SCB and OB in visual comparison tasks that required judging whether two objects were
the same or different. Each trial consisted of two sequential displays (S1 and S2). Each display
contained a 3x3 grid with a target object in the middle row and two distractor objects, one in
the top row and one in the bottom row. Participants judged whether the shape and/or position
of a target object was the same or different in S1 and S2. There were two key manipulations
common to both studies. Firstly, within every experiment the relative location of the grid
between S1 and S2 was manipulated to assess the SCB. The grid was in the same location from
S1 to S2 on half the trials and a different location on the remaining trials. Secondly, between
experiments, the similarity of the distractor objects was manipulated with respect to the task
relevant feature (i.e., their shape in the shape judgement task and their position in the position
judgment task). The distractor objects either remained the same from S1 to S2 on most trials
(high similarity) or they changed from S1 to S2 on all trials (low similarity).
Study 1 was designed to investigate how location and display similarity affect response
biases, and how those effects differ for position judgements versus shape judgements. Previous
research has focused on investigating the SCB in judgments of object features such as shape
and colour. In the first two experiments the task moved beyond feature comparisons, requiring
comparison of the local position of the target (a black dot) with displays that had high similarity
(Experiment 1) or low similarity (Experiment 2). The next two experiments directly compared
the SCB and OB in position judgments versus shape judgments in within-subjects designs using
letter stimuli; again, displays had high similarity (Experiment 3) or low similarity (Experiment
4). Together, the results of these experiments revealed that the SCB is a general phenomenon
that applies to both position and shape comparisons, and is consistent regardless of stimulus
type (dot or letter). Further, the SCB was weakened and the OB shifted more towards
“different” when similarity was low, and the OB was shifted more towards “same” in position
versus shape comparisons. The pattern of results suggests the SCB indexes the operation of a
visual heuristic that is linked to the privileged nature of location and is evoked more often when
similarity is high. Furthermore, as attentional selection requirements increase, due to the nature
of the task and/or differences between displays, the tendency for “different” response increases.
Study 2 was designed to determine whether an attentional mechanisms account, in
which bias is modulated via adjustments to attentional zoom, or an overlap measure account,
in which bias is modulated via an interaction between the number of differences and the
threshold for a “different” response, is more parsimonious as an explanation for the effect of
similarity on response bias. Previous research has indicated that the extent of attentional focus
is adjusted to optimise target selection when the position of the target is predictable. In four
experiments the position of the target letter was manipulated in the shape comparison task: it
either remained in the same position from S1 to S2 or changed position, and this manipulation
was either predictable (Experiments 5 and 7) or unpredictable (Experiment 6 and 8). Further,
distractor similarity again varied from high (Experiments 5 and 6) to low (Experiments 7 and
8). The results revealed that reduced similarity affects response bias when either distractor
shape or target position changes, and the predictability of target position only modulates bias
when distractor similarity is low. The pattern of results suggests that mechanisms inherent in
the overlap measure account provide a sufficient explanation for variation in response bias
when holistic processing is possible, and that attentional mechanisms play an important role
when analytic processing is required.
In summary, a complex interaction between multiple factors influences response bias
in visual comparisons. The SCB manifests as a result of the privileged nature of location
which underpins a key heuristic, “same-location = same-object”, and the strength with which
this heuristic is evoked varies with overall display similarity and attentional zoom settings.
Visual similarity influences both the operation of the heuristic and the overall tendency for a
“different” response via an interaction between the overlap measure, a “difference count”
from the direct comparison of two displays, and the threshold for a “different” response, that
develops on the basis of the heterogeneity of differences across multiple trials. Both biases
are further modulated by attentional mechanisms that operate to adjust attentional zoom
settings when experience with the task and/or displays indicates that analytic processing is
optimal.