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Migration and spawning strategies of hilsa shad (Tenualosa ilisha, Clupeidae) in the Ayeyarwady River revealed by otolith chemistry
Full text linkHilsa shad (Tenualosa ilisha) is an ecologically and economically important fish species in the Indo-Pacific region, yet its migration and spawning behaviour remains poorly in Myanmar. This study investigates hilsa migration and spawning strategies in the Ayeyarwady River using otolith chemistry, including elemental ratios (Sr:Ca, Ba:Ca, Mg:Ca, Mn:Ca) and 87Sr:86Sr isotope signatures. Otoliths from 101 juvenile and adult hilsa collected across the Ayeyarwady River Basin showed that 94 % of hilsa exhibited life histories consistent with anadromy (spawning in freshwater rivers but growing up in the ocean). However, a small subset (6 %) displayed alternative reproductive strategies, likely spawning in higher salinity environments (such as estuarine or coastal areas) without entering rivers. Additionally, hilsa may migrate over 1500 km to the Upper Ayeyarwady from the sea. Additionally, otoliths of juvenile hilsa collected in the Chindwin River, exhibited consistently low Sr:Ca ratios along the core-to-edge profiles, indicating prolonged freshwater residency post-hatching (up to six months). Findings from this study illustrate the predominance of an anadromous life history and the existence of an alternative reproductive strategy, which are essential for adaptive management and conservation of hilsa in Myanmar. Given the species’ trans-boundary distribution and importance in the Indo-Pacific region, effective fishery management requires strengthening regional cooperation to promote sustainable hilsa fisheries in the region
Long-term effects of vegetation cover on the rehabilitation of lead/zinc mine tailings
Full text linkPb/Zn sulfide ore is extracted from carbonate host rock by milling to grainsizes <120 μm and separation by flotation. This produces large volumes of near neutral pH tailings that must be carefully managed due to regulatory concern about the residual Pb and Zn concentrations (up to ∼0.3 % by wt. of each) and trace concentrations of other potentially toxic elements. To prevent dust formation, vegetation cover is established on inactive areas of the tailings management facility (TMF). This paper reports the changes in the chemical and microbiological composition of the tailings as a function of both time and depth. Over the course of eight years, there is progressive oxidation of pyrite in the tailings, and accumulation of soil organic matter in the surface layers. The mobility of most potentially toxic elements is reduced due to sorption to ferric oxyhydroxides formed as a result of pyrite oxidation, although Cu is more mobile in surface layers probably due to formation of dissolved organic carbon complexes. The microbial community diversity in the surface layer increased with the age of the tailings and was similar to natural calcareous soil after 8 years. At this age the functional profile (functional diversity) of the community was similar to that of natural calcareous soil, despite differences remaining in taxonomic composition. Development of soil-like properties in the surface layer, such as increased soil organic matter content and a soil-like microbial community, suggest that the vegetation cover will be self-sustaining. Therefore, revegetation is a viable option for TMF closure planning
Teacher to Researcher: supporting pupils mental health and well-being with a whole-school approach. Pre-intervention correlation coefficient data
No full textThis dataset provides all the original data to support readers to engage with the full data set associated with this project. In related publications the aspect of this data that is reported is the strength of the correlation relationship and the final r value. Spreadsheet of anonymised and coded responses (n=106)
The relationship between language disorder and thought disorder: Comparing micro- and macrostructure of spoken narratives of people with aphasia and people with schizophrenia
Full text linkLinguistic profiles in neurological and psychiatric conditions offer critical insights into the relationship between language and broader cognitive functions. People with aphasia (PwA) can display severe language production and comprehension difficulties, often alongside relatively preserved capacity in other domains. In contrast, people with schizophrenia (PwS) can present with disordered thoughts, delusions and hallucinations, accompanied by atypical language use. We examined microstructural (lexicon, syntax) and macrostructural (narrative) features of comic strip descriptions produced by PwA, PwS, and two respective control samples, using manual annotation and computerized tools. Both clinical groups diverged from controls at microstructural and macrostructural levels. However, PwA showed greater microstructural disruption, while PwS exhibited greater macrostructural impairment. Language production in PwA differed most from PwS in the much higher rate of morphosyntactic errors, more frequent intra-clausal pauses, and a greater reduction of grammatical complexity. In PwA, performance in non-verbal reasoning and semantics tests correlated with macrostructural, but not with microstructural measures. In PwS, non-verbal reasoning scores correlated with both micro- and macrostructural measures. These findings highlight distinct effects of more focal left perisylvian damage associated with aphasia, versus diffuse bihemispheric frontotemporal and parietal dysfunction associated with schizophrenia, on cognition and communication. We propose that verbal disruption with few morphosyntactic errors and intra-clausal pauses reflects broader cognitive dysfunction, whereas a high frequency of these features points to difficulties more specific to language production and comprehension
Content validity of the birth beliefs scale following a translation into German
Full text linkObjectiveThis study aimed to translate and adapt the Birth Beliefs Scale (BBS) into German, focusing on content validity of the German version (G-BBS). The BBS, originally developed in Israel and validated in English, assesses women’s basic beliefs about childbirth.MethodsThe translation and adaption followed the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) guideline. Four translators were involved in forward and backward translation. Content validity procedures were aligned with COSMIN (COnsensus-based Standards for the selection of health Measurement Instruments) methodology. Cognitive debriefing involved 10 experts and 30 pregnant women for content validity. Both groups rated relevance, clarity as an indicator of comprehensibility, and overall comprehensiveness.ResultsMinor harmonization adjustments were required to enhance clarity, particularly in specific items, but no major revisions were required. Content validity index scores were acceptable for 10 out of 11 items during harmonization. During the validation process minor revisions were needed for two items. Inter-rater agreement from the expert panel and the target group exceeded 80%, confirming the adaption’s clarity and cultural relevance. Pregnant participants rated the scale as easy to use. Overall comprehensiveness was confirmed by both groups.ConclusionThe BBS was systematically translated and adapted for German users, incorporating harmonization procedures to ensure conceptual equivalence as well as linguistic and cultural appropriateness throughout the translation process.Further psychometric validation in a larger sample is needed to evaluate structural properties and measurement performance
Effects of graded-porosity gas diffusion layers used in polymer electrolyte fuel cells
Full text linkOptimising the design of gas diffusion layers (GDLs) is essential to enhance water management and reactant transport in polymer electrolyte fuel cells (PEFCs), which are critical renewable energy conversion technologies required to decarbonise electricity. In this work, a comprehensive three-dimensional model of a PEFC has been developed to analyse the sensitivity of fuel cell performance to graded-porosity cathode GDLs under various humidity conditions and GDL thicknesses. The results show that, for most humidity conditions, the fuel cell performs best when the cathode GDL has low porosity at the catalyst interface and high porosity at the bipolar plate interface. Under relatively low humidity conditions, fuel cell performance deteriorates when using graded-porosity GDLs with higher porosity near the catalyst layer. On the other hand, under high humidity conditions, a cathode GDL with a porosity gradient improves performance compared to a GDL with uniform porosity. Further, when the GDL thickness is reduced from 300 μm to 200 μm, the best performance is achieved with a GDL that has higher porosity near the catalyst layer. These findings are discussed and justified in the study providing valuable guidance for designing advanced GDL structures to improve PEFC efficiency, supporting their wider adoption in renewable energy systems
Implications of retailer-owned digital twins services: The trade-offs between customer experience, misfit returns reduction, and investment costs
No full textMany prominent retailers, including Walmart, Kroger, IKEA, and Amazon, utilize Digital Twins (DTs) to enhance customer experience and reduce misfit returns by creating virtual replicas of products, service systems, shopping environments, and customer interactions. However, prior studies on DTs have mainly centered on applications within the manufacturing sectors, thereby overlooking the development of DT services owned or operated by retailers. To fill this gap, our models analyze how retailer-owned DT service is shaped by the trade-off between customer experience, misfit returns reduction and investment expenditures, as well as investigate its impact on the manufacturer's equilibrium decisions and profits. Our analysis indicates that higher levels of product misfit and consumer return losses incentivize retailers to adopt DTs. Furthermore, although retailer-owned DT may benefit manufacturers and lead to Pareto improvements, manufacturers should be cautious, as higher DT adoption costs for ‘inefficient’ retailers can result in a win-lose situation. This occurs because retailer-owned DTs, while potentially enhancing the manufacturer's equilibrium quality and wholesale prices, can also incentivize ‘inefficient’ retailers to raise retail prices further, which reduces the optimal sales volume and negatively impacts the manufacturer's overall profits. In addition to confirming the robustness of our main findings, our two extensions further reveal that, (i) there is an inverted U-shaped relationship between retailers' incentives for DT adoption and consumers' privacy concerns, and (ii) previous-period misfit returns diminish retailers' incentives for DT adoption
The late Permian through Middle Triassic environmental crises in the Boreal Realm – Records of the Griesbachian, Dienerian, Smithian, and Spathian type sections in Arctic Canada
Full text linkOur understanding of the greatest biologic catastrophe in Earth history, the Permian/Triassic mass extinction, is largely informed by extensive studies of highly fossiliferous sedimentary records from the Tethys Ocean. Deposited on the eastern equatorial margin of the Pangea supercontinent, Tethyan sediments record the dramatic devastation of ecosystems across the Permian/Triassic boundary, and the long, slow recovery that characterizes its aftermath. In contrast, the western margin of Pangea has a sparse fossil record, but it provides important insights into the dynamic changes in biogeochemical and nutrient cycles that occurred during the extinction. Here we examine chemostratigraphic and geochemical records from the northwestern margin of Pangea, with a focus on the type sections of the Griesbachian, Dienerian, Smithian, and Spathian (the four substages of the Lower Triassic), the sediments of which were deposited in the Sverdrup Basin which now lies in the Canadian Arctic Archipelago. We show that northwest Pangea, was under growing environmental stress prior to the mass extinction, where Boreal depositional systems were marked by the eradication of carbonate producers and progressive occupation of shallow shelf environments by siliceous sponges. The Siberian Traps erupted into this already stressed world driving shallow to deep water marine anoxia. Following the extinction, the Early Triassic was an interval of major perturbations in global biogeochemical cycles, defining several aborted recoveries including the Smithian hyperthermal event and subsequent Spathian negative carbon isotope excursion. Final stabilisation of marine environments occurred in the Middle Triassic, marked by massive carbon drawdown sequestered as marine algae
High Trait Procrastination Predicts Increased Goal Anxiety Despite Invariance in Simulation of Goal Achievement
No full textProcrastination is a self-regulatory failure in which important tasks are delayed despite the knowledge that this is unhelpful; episodic future thinking is the process of constructing detailed mental simulations of possible future events. High trait procrastination has been linked to reduced sensory-perceptual detail when simulating future events based on experimenter prompts, yet it remains unclear if this extends to events reflecting achievement of one’s personal goals. The present investigation aimed to establish the relations between trait procrastination and attributes of short-term (6months) personal goals and goal achievement simulations. High procrastination was expected to predict high self-reported likelihood of goal avoidance, especially for long-term goals (due to associated delay sensitivity); reduced sensory-perceptual detail in achievement simulations; and heightened anticipatory anxiety when contemplating goal failure. Multilevel models controlling for other goal attributes showed a positive predictive effect of procrastination on avoidance likelihood for long- and short-term goals; no effects on sensory-perceptual detail of achievement simulations; and a positive predictive effect on anticipatory anxiety which was most pronounced for short-term goals. Exploratory analyses further showed that neither goal importance nor achievement simulation characteristics (autonoetic consciousness, anticipated emotions) were sensitive to procrastination levels. These findings suggest that a tendency to procrastinate, though disruptive, does not imply deficits in goal setting; and further, that its effects on future simulation may not extend to personally important goal-related events. Finally, results on anticipatory anxiety highlight a potential mechanism by which high procrastinators are drawn into focussing on short-term goals at the expense of more important long-term priorities
Dynamical disequilibrium in dwarf galaxies: rethinking gas dynamics, rotation curves, and dark matter inference
No full textWe quantify departures from hydrodynamical and centrifugal equilibrium in the g as discs of low-mass ( 10 10 . 75 < M 200c / M < 10 11 ) galaxies from the COLIBRE cosmological hydrodynamical simulations. We evaluate the full Eulerian acceleration balance in the mid-plane and show that disequilibrium is widespread: equilibrium-based circular velocity estimates typically have errors of ≥10 per cent ( ≈75 per cent of mid-plane gas by mass). Disequilibrium is strongest and the largest associated errors occur in the inner few kiloparsecs that are crucial for constraining the dark matter density profile. Correcting the circular velocity to account for pressure and convective terms does not reliably improve its recovery in strongly perturbed systems where time-dependent forces dominate the residual acceleration budget. Stellar feedback, self-gravitating gas clumps, and active galactic nucleus energy injection account for most strong local perturbations, and large-scale gravitational asymmetries act as a scaffold for disequilibrium. We classify gas discs into coherent, perturbed, and slow/erratic rotators and show that this classification correlates with galaxy properties like mass, morphology, and tracers of recent feedback. A majority of galaxies in our sample would be unsuitable for standard rotation curve analysis. Much of the observed diversity in the shapes of dwarf galaxy rotation curves may stem from non-equilibrium g as motions rather than diversity in mass profiles –resolving the discrepancy is then first and foremost a problem in gas dynamics