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Microplastics in the Southern Brazilian estuary : Interactions between environment, morphology, and seasonal variation
No full textEstuaries are complex environments rich in biodiversity, making it challenging to understand the distribution and occurrence of microplastics due to the multiple variables that can influence the movement of these particles. Based on this, this study evaluated the influence of different environmental aspects on the distribution and transport of microplastics in the surface waters of the Tramandaí River estuary. An average occurrence of 14.21 ± 3.07 items L−1 was identified, with a predominance of white/transparent fibers smaller than 500 µm in size. PE and PP were the predominant polymers with an average carbonyl index (CI) of 0.77 ± 0.41. From the results, it was observed that periods with little rainfall can decrease the occurrence of microplastics in the surface water of the studied estuary but increase the predominance of white or colorless particles and fragments. Additionally, anthropogenic activity and water depth influenced the occurrence and form of particles in the surface waters. Furthermore, the progressive approach to the sea decreased the occurrence of blue microplastics and increased the abundance of smaller particles. Finally, the change in tides directly impacted only the estuary point, influencing the occurrence and shape of the particles. Thus, the results demonstrated that several factors interfered with the abundance and characteristics of the microplastics found in the Tramandaí River basin. The estuary point was influenced by the largest number of variables, highlighting the complexity of these environments. Additionally, the importance of evaluating not only aspects intrinsic to the sampling site but also seasonal factors was emphasized
Occupational exposure to chemicals and particles and incidence of myocardial infarction—a nationwide cohort study in Sweden
No full textCardiovascular disease (CVD) is the leading cause of death in Europe, with myocardial infarction (MI) being one of its most severe manifestations. While many risk factors for CVD are well known, occupational exposures remain relatively understudied—especially in analyses that adjust for co-occurring workplace exposures. This study aimed to examine the association between occupational exposure to chemicals and particles and the risk of first-time MI. The cohort included all Swedish residents born between 1930 and 1990 who were employed between 1985 and 2013 and had no prior MI. Participants were followed from 1986 to 2017, and their occupational histories were linked to the Swedish Job Exposure Matrix (SweJEM) to estimate exposure to 31 chemicals and particles. MI cases were identified through national hospital discharge and cause of death registers. Using discrete time proportional hazards regression, we estimated gender-specific hazard ratios, adjusting for age, decision authority, physical workload, noise, other chemicals/particles, and within a subset smoking and body mass index (BMI). Among 225,366 incident MI cases, the strongest increased risk was associated with both cumulative, ever, and recent exposure to diesel exhaust, polycyclic aromatic hydrocarbons, sulphur dioxide, carbon dioxide, cadmium, chromium, iron, and lead. These associations remained after adjusting for smoking, BMI, and education. Hazard ratios were generally higher among women. The attributable proportion among exposed individuals was 9 %, corresponding to over 20,000 cases during the follow-up period. Our findings highlight the importance of reducing occupational exposure to harmful substances to prevent future cases of MI
Statistical Data Analysis of Inspection Outcomes of Post-Tensioned Concrete Bridges in Italy
No full textCorrosion of cables can result in brittle and unexpected failures and represents a critical concern for prestressed concrete bridges with post-tensioned (PT) tendons. In these structures, corrosion is typically facilitated by inadequate grout injection and/or the use of poor-quality mortar during construction. Such deficiencies create favorable conditions for corrosion initiation and propagation. Furthermore, injection voids are not detectable through visual inspections, implying that both the number and location of these defects are characterized by significant uncertainty. Considering these challenges, the present paper presents the statistical analyses conducted on a comprehensive dataset compiled from numerous inspection reports of existing PT bridges across Italy, with the aim of better addressing the inspections and especially developing probabilistic models useful for reliability analysis of these structures
Mapping the solution space for local adaptation under global change : An test of concept for the Vietnamese Mekong delta
No full textCurrent and projected environmental changes are complex and unprecedented in the context of modern societies. Effective adaptation strategies must consider constraining and enabling factors from both physical and societal aspects, as well as associated uncertainties at different points in time. Here we present a multidisciplinary method to quantify the solution space for individual adaptation measures—a conceptual space describing the feasibility of effectively implementing an adaptation measure, bounded by physical and societal constraints. Solution spaces can be projected over time under different scenarios and for multiple adaptation measures to identify what measures are available at any point, when the solution space changes (enabling or disabling choices), and what can be done to expand the space. We demonstrate the method for an illustrative case study of the coastal Mekong delta in Vietnam, an area with intense overlapping drivers of relative sea-level rise increasing coastal flooding. We consider three adaptation measures (mangroves, dikes, retreat) over the 21st century. The implementation reveals critical conditions for adaptation strategies, and when they might become infeasible without enabling actions. Our novel systematic approach can be implemented in real-world cases using data from the specific case of interest to assess the feasibility of measures determined by the (bio)physical, socio-economic, governance and legislation context, and provides insight into adaptation limitations and measures to maintain and/or expand the solution space. Such a multi-dimensional assessment is challenging due to the identification of critical conditions for many different dimensions, but is valuable to evaluate adaptation potential and design adaptive pathways plans to deal with uncertain changing conditions
Ventilation in Adaptive Reuse : Reducing uncertainty in concept-stage decisions
No full textDecarbonisation of the built environment requires alternatives to the prevailing practice of demolition followed by new construction. The new production of buildings adds upfront embodied emissions, while much of the non-residential stock remains underutilised, and housing demand remains high. Adaptive reuse, the practice of converting existing buildings for new functions, preserves the building's envelope and structural frame, and may retain its building services, thereby avoiding embodied emissions and capital costs. Ventilation equipment can be reused or adapted; however, concept-stage planning often defaults to full replacement of it. Early design decisions, therefore, determine whether reuse is seen as viable and what material and cost consequences follow.This thesis develops a framework for retaining or adapting ventilation in conversion projects, providing structured decision support to reduce uncertainty at the conceptual stage. The thesis comprises three strands. First, a building stock strand reconstructs pre- and post-conversion building pairs from national Energy Performance Certificates (EPCs). This is done to identify conversion pathways and describe the dominant ventilation concept, as well as the declared airflow. Second, a feasibility strand compares ventilation requirements from earlier and current Swedish building regulations. This strand also uses interview data to capture practitioners’ perspectives on when reuse is acceptable and how responsibilities are allocated. Third, a design-science strand develops a ventilation-aligned, low-intervention design (VALID) sequence that screens functional programme-layout compatibility, aligns high-demand rooms with existing supply terminals, and assesses consequences through scenario-based LCC and LCA limited to stages A1–A5.Three results follow. Stock-scale conversions concentrate on office-to-residential and retail-linked pathways. Within these, EPCs tend to indicate retention of the ventilation concept, and where paired changes in declared airflow are detectable, reductions dominate. The feasibility strand suggests that office-to-apartment, school-to-apartment, and school-to-office pairs may meet contemporary outdoor air requirements without altering the ventilation concept. Practitioners state that reuse is acceptable when performance, cleanliness, airtightness, origin and documentation of the ventilation systems can be verified. Applying the screen-align-appraise method to an office-to-residential case enables a large portion of the existing ventilation system to be retained, resulting in reductions in carbon emissions (stages A1–A5) and construction costs compared to full replacement. A workshop-based screening of a pre-school-to-elderly care case led to rejecting the conversion because the required functional divisions and adjacencies could not be accommodated within the as-found layout.The primary contribution of this thesis is the reduction of concept-stage uncertainty in adaptive reuse projects with a focus on ventilation. This is achieved by establishing a national baseline for conversion pathways and ventilation characteristics within these pathways, developing a feasibility framework that translates regulations and acceptance procedures into project-level conditions for reuse, and conceptualising a low-intervention conversion method that focuses on preserving existing supply-air systems and reporting ranges of environmental and cost outcomes. This approach can support lower-intervention conversions where hygiene, airtightness and documentation requirements are met
Historical foraminiferal collections as a resource for monitoring anthropogenic climate change
No full textNatural history museum collections (NHC) represent an underutilized yet valuable resource for tracking environmental changes and anthropogenic impacts on marine ecosystems. Historical samples, particularly foraminifera collected during marine expeditions from the late 1800s to mid-1900s, offer crucial baseline data pre-dating significant human influence. These collections, often accompanied by oceanographic data, can fill important knowledge gaps regarding past biodiversity, species distribution, and ecosystem health. While challenges such as limited accessibility, uncertain sample histories, and methodological inconsistencies exist, modern analytical approaches, including non-destructive imaging and machine learning, greatly enhance their usability. Here we advocate for the preservation, digitization, and strategic use of historical micropaleontological collections, emphasizing their potential for providing essential long-term ecological insights and supporting conservation and climate mitigation strategies
A large-scale multi-centre study characterising atrophy heterogeneity in Alzheimer's disease
No full textPrevious studies identified atrophy-based Alzheimer's disease(AD) subtypes linked to distinct clinical symptoms, but their consistency across subtyping approaches remains unclear. This large-scale study evaluates subtype concordance using two data-driven approaches. In this work, we analyzed data from n=10,011 patients across 10 AD cohorts spanning Europe, the US, and Australia, extracting regional volumes using Freesurfer. To characterize atrophy heterogeneity in the AD continuum, we developed a two-step approach, Snowphlake (Staging NeurOdegeneration With PHenotype informed progression timeLine of biomarKErs), to identify subtypes and atrophy-event sequences within each subtype. Results were compared with SuStaIn (Subtype and Stage Inference), which jointly estimates subtypes and staging, using similar training and validation. Training included Aβ+ participants (n=1,195) and Aβ− cognitively unimpaired controls (n=1,692). We validated model-staging in a held-out clinical dataset (n=6,362) and an independent dataset (n=762), and assessed clinical significance in Aβ+ subsets(n=1,796 held-out; n=159 external). Concordance analysis evaluated consistency between methods. In the AD dementia(AD-D) training data, both Snowphlake and SuStaIn identified four subtypes. In the validation datasets, staging with both methods correlated with Mini-Mental State Examination(MMSE) scores. The Snowphlake subtypes assigned in Aβ+ validation datasets were associated with alterations in specific cognitive domains(Cohen's f: [0.15−0.33]). Similarly, the SuStaIn subtypes were also associated specific cognitive domains(Cohen's f:[0.17−0.34]). However, we observed low concordance between Snowphlake and SuStaIn, with 39.7% of AD-D patients grouped in concordant subtypes by both methods. In conclusion, Snowphlake and SuStaIn identified four atrophy-based subtypes that linked to distinct symptom profiles. While this highlights that the neuro-anatomically defined subtypes also meaningfully associate with different cognitive impairments at a group level, the low concordance between methods suggests that future research is needed to better understand the biological and methodological factors contributing to the observed variability
Perspectivas de estudiantes universitarios suecos sobre la lectura de La ciudad y los perros : Un proyecto de diarios de lectura
No full textReading Mario Vargas Llosa's The time of the hero is a challenge for Swedish university students of Spanish as a foreign language, but despite this, course evaluations have shown that they tend to value the experience. This study focuses on exploring the students’ reading process and their reactions to the text through a reading log project. The categories of recognition, knowledge, enchantment and shock proposed by Felski (2008) were applied to analyse the students' responses. The analysis indicates that the students’ preferred way to check their understanding and interpretation of the literary text was to discuss the reading with their peers. It also indicates that, despite the linguistic difficulties, the participants experienced a complex aesthetic response, reacting intensely to the characters and often shocking situations in the novel. However, the main motivator in play in the reading process seems to have been the desire to reconstruct a coherent story from the narrative fragments, filling in the gaps to solve the central enigma of the plot. This reconstruction was greatly aided by reading together, and one of the conclusions of the study is that it is beneficial to think of reading as a collective act
Advances, challenges, and opportunities of human midbrain organoids for modelling of the dopaminergic system
No full textDopaminergic neurons in the ventral midbrain are critical for regulating movement, cognition, and emotion. Ventral midbrain organoids can be used to model both development and diseases of the dopaminergic system, especially Parkinson’s disease. Here, we summarize recent advances and remaining challenges in developing such three-dimensional organoids from human pluripotent stem cells. We outline how ventral midbrain organoid systems have progressed from early three-dimensional culture models to sophisticated, engineered, multiregional systems that more accurately replicate the complex network of dopaminergic neurons. Furthermore, we examine how the development of organoid models from other brain regions, particularly the forebrain, provides complementary insights that can accelerate progress also in the field of midbrain organoids, towards the generation of more advanced in vitro systems for midbrain dopaminergic neurons and their circuitry. Such cutting-edge human stem cell-based models offer powerful platforms for investigating dopaminergic neuron generation, function, and connectivity, thereby enhancing disease modelling, drug discovery, and the development of targeted cell-based therapies
How monitoring of atom bomb tests can reveal timing of moss dispersal!
No full textWe recently published an article that demonstrates how eDNA can reveal shifts in the annual timing of wind-carried dispersal agents (spores) of mosses and liverworts