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Deciphering the Complex Alteration Recorded in Primitive Asteroids
CM chondrites are unequilibrated breccias sampling primitive asteroids altered by water-rock interactions. While much research has focused on bulk measurements, only tentative attempts have been made to elucidate the complex petrographic and O-isotopic heterogeneity at the clast and component scale utilising this high precision approach.
Clasts of petrologic subtype CM1/2.0 – 2.8 were found in four falls and one very diverse find, LON 94101, the latter of which strengthens the case of a discrete parent body source for CM chondrites. The petrologic subtype of moderately altered clasts ranging from 2.2-2.6 appear to correlate well with variable ‘FeO’/SiO2 and Mg# compositions within their phyllosilicates, though this is poorly matched from meteorite to meteorite. Fully altered clasts (CM1/CM2.0) host an array of diverse textures ranging from dark, Mg-dominated matrix-rich clasts to those containing abundant chondrule pseudomorphs, comparable in large part to the diversity seen in CM2 material. An array of rarer, petrographically distinct lithologies, including incipiently altered, predominantly anhydrous examples, attest to the diversity of CM material in the meteorite record.
Matrix phyllosilicates from 30 petrographically characterised CM lithologies and 4 cataclastic matrix fractions were micro-sampled to investigate lithology-specific aqueous alteration phenomena through their O-isotopes, obtained via a revised laser fluorination protocol for small, phyllosilicate-rich samples. The exclusion of a significant anhydrous precursor component within these fractions reveals a novel, apparently mass-dependent trend: the CM matrix fractionation line (CMF) at ~ Δ17O = -2.35 ± 0.46‰ (2σ), indicating the CM lithologies were altered within a narrow range of water to rock (WR) ratios and that historical O-isotope variation primarily just reflects variable amounts of anhydrous precursor. This weakens the case for a closed system style of alteration, where variable WR ratios may be expected; indeed, an open system may provide a better explanation where equilibration of water is achieved over a mineralogically diverse area on the CM asteroid
Blurring the Boundaries Between Medicine and Food: The Canny Marketing of Läkerol in Early Twentieth-Century Sweden
This paper explores the early marketing practices (1910-1940) of the Swedish cough drop brand Läkerol, demonstrating how it capitalised on the “spaces of confusion” posed by the product’s liminality between food and medicine to create a slick marketing campaign inspired by the tried-and-tested formulas of the food industry. Advertisements used a range of strategies, such as expert and role model testimonials, humorous and serious newsjacking and the introduction of a friend-physician brand mascot to extend Läkerol from a cold remedy to an everyday product necessary for fun and excitement. By telling consumers not just about its benefits, but also connoting that it was part of a contemporary way of living, Läkerol was able to incorporate itself into a daily consumerist lifestyle, growing into a trendy and popular brand consumed daily by Swedes as part of a ritualised practice
Realising the potential of online teacher development courses to improve student learning: lessons for Local Education Officers
The Government of Bangladesh is making substantial investment in blended learning for teachers. Teachers undertake face-to-face trainings in Continuous Professional Development (CPD) priority areas, such as supporting students’ foundational learning. In parallel, teachers access TPD courses on Muktopaath, an eLearning platform, focused on these same priority areas. Local Education Officers have a pivotal role in the delivery of these trainings and in supporting their practical application in schools and classrooms. This Policy Brief explores teachers’ participation in one set of eLearning courses, Anonde Gonit Shikhi (AGS). It makes evidence-based recommendations on how Local Education Officers at District and Upazila levels can encourage and support teachers to translate learning from both the online courses and face-to-face trainings into the intended changes in teaching practices and student learning in the classroom
Discussing the Changing Landscape of Generative AI in Computing Education
In a previous Birds of a Feather discussion, we delved into the nascent applications of generative AI, contemplating its potential and speculating on future trajectories. Since then, the landscape has continued to evolve revealing the capabilities and limitations of these models. Despite this progress, the computing education research community still faces uncertainty around pivotal aspects such as (1) academic integrity and assessments, (2) curricular adaptations, (3) pedagogical strategies, and (4) the competencies students require to instill responsible use of these tools. The goal of this Birds of a Feather discussion is to unravel these pressing and persistent issues with computing educators and researchers, fostering a collaborative exploration of strategies to navigate the educational implications of advancing generative AI technologies. Aligned with this goal of building an inclusive learning community, our BoF is led by globally distributed leaders to facilitate multiple coordinated discussions that can lead to a broader conversation about the role of LLMs in CS education
Defining the hidden burden of disease in rural communities in Bangladesh, Cambodia and Thailand: a cross-sectional household health survey protocol
Introduction In low-income and middle-income countries in Southeast Asia, the burden of diseases among rural population remains poorly understood, posing a challenge for effective healthcare prioritisation and resource allocation. Addressing this knowledge gap, the South and Southeast Asia Community-based Trials Network (SEACTN) will undertake a survey that aims to determine the prevalence of a wide range of non-communicable and communicable diseases, as one of the key initiatives of its first project-the Rural Febrile Illness project (RFI). This survey, alongside other RFI studies that explore fever aetiology, leading causes of mortality, and establishing village and health facility maps and profiles, will provide an updated epidemiological background of the rural areas where the network is operational.
Methods and analysis During 2022-2023, a cross-sectional household survey will be conducted across three SEACTN sites in Bangladesh, Cambodia and Thailand. Using a two-stage cluster-sampling approach, we will employ a probability-proportional-to-size sample method for village, and a simple random sample for household, selection, enrolling all members from the selected households. Approximately 1500 participants will be enrolled per country. Participants will undergo questionnaire interview, physical examination and haemoglobin point-of-care testing. Blood samples will be collected and sent to central laboratories to test for chronic and acute infections, and biomarkers associated with cardiovascular disease, and diabetes. Prevalences will be presented as an overall estimate by country, and stratified and compared across sites and participants' sociodemographic characteristics. Associations between disease status, risk factors and other characteristics will be explored.
Ethics and dissemination This study protocol has been approved by the Oxford Tropical Research Ethics Committee, National Research Ethics Committee of Bangladesh Medical Research Council, the Cambodian National Ethics Committee for Health Research, the Chiang Rai Provincial Public Health Research Ethical Committee. The results will be disseminated via the local health authorities and partners, peer-reviewed journals and conference presentations.
Trial registration number NCT05389540
IQGAP1 and NWASP promote human cancer cell dissemination and metastasis by regulating β1-integrin via FAK and MRTF/SRF
Attachment of circulating tumor cells to the endothelial cells (ECs) lining blood vessels is a critical step in cancer metastatic colonization, which leads to metastatic outgrowth. Breast and prostate cancers are common malignancies in women and men, respectively. Here, we observe that β1-integrin is required for human prostate and breast cancer cell adhesion to ECs under shear-stress conditions in vitro and to lung blood vessel ECs in vivo. We identify IQGAP1 and neural Wiskott-Aldrich syndrome protein (NWASP) as regulators of β1-integrin transcription and protein expression in prostate and breast cancer cells. IQGAP1 and NWASP depletion in cancer cells decreases adhesion to ECs in vitro and retention in the lung vasculature and metastatic lung nodule formation in vivo. Mechanistically, NWASP and IQGAP1 act downstream of Cdc42 to increase β1-integrin expression both via extracellular signal-regulated kinase (ERK)/focal adhesion kinase signaling at the protein level and by myocardin-related transcription factor/serum response factor (SRF) transcriptionally. Our results identify IQGAP1 and NWASP as potential therapeutic targets to reduce early metastatic dissemination
Performance of a simplified strategy for formula constant optimisation in intraocular lens power calculation
Purpose: To investigate the performance of a simple prediction scheme for the formula constants optimised for a mean refractive prediction error.
Methods: Analysis based on a dataset of 888 eyes before and after cataract surgery with IOL implantation (Hoya Vivinex). IOLMaster 700 biometric data, power of the implanted lens and postoperative spherical equivalent refraction were used to calculate the optimised constants (.)opt for SRKT, HofferQ, Holladay and Haigis formula with an iterative nonlinear optimisation. For detuning start values by ±1.5 from (.)opt, the predicted formula constants (.)pred were calculated and compared with (.)opt. Formula performance metrics mean (MPE), median (MEDPE), mean absolute (MAPE), median absolute (MEDAPE), root mean squared (RMSPE) and standard deviation (SDPE) of the formula prediction error were analysed for (.)opt and (.)pred.
Results: (.)pred – (.)opt showed a 2nd order parabolic behaviour with maximal deviations up to 0.09 at the tails of detuning and a minimal deviation up to −0.01 for all formulae. The performance curves of different metrics of PE as functions of detuning variations show that the formula constants for zeroing MPE and MEDPE yield almost identical formula constants, optimisation for MAPE, MEDAPE and RMSPE yielded formula constants very close to (.)opt, and optimisation for SDPE could result in formula constants up to 0.5 off (.)opt which is unacceptable for clinical use.
Conclusion: This simple prediction scheme for formula constant optimisation for zero mean refraction error performs excellently in our monocentric dataset, even for larger deviations of the start value from (.)opt. Further studies with multicentric data and larger sample sizes are required to investigate the performance in a clinical setting further
New insights into morphological adaptation in common mole‐rats (<i>Cryptomys hottentotus hottentotus</i>) along an aridity gradient
Morphological adaptation is the change in the form of an organism that benefits the individual in its current habitat. Mole‐rats (family Bathyergidae), despite being subterranean, are impacted by both local and broad‐scale environmental conditions that occur above ground. Common mole‐rats (Cryptomys hottentotus hottentotus) present an ideal mammalian model system for the study of morphological variation in response to ecology, as this species is found along an aridity gradient and thus can be sampled from geographically non‐overlapping populations of the same species along an environmental longitudinal cline. Using the mass of five internal organs, ten skeletal measurements and 3D morphometric analyses of skulls, we assessed the morphology of wild non‐breeding individuals from five common mole‐rat populations in South Africa. We found that the body mass and mean relative mass of the spleen and kidneys in arid populations was larger, and individuals from arid regions possessed shorter legs and larger inter‐shoulder widths compared to individuals from mesic regions. Additionally, arid populations demonstrated greater skull depth, and shape change of features such as angular processes of the lower jaw than mesic individuals, indicating that these distinct geographic populations show differences corresponding to the aridity gradient, potentially in response to environmental factors such as the variation in food sources found between different habitats, in addition to different soil compositions found in the different regions. Arid populations potentially require a stronger jaw and neck musculature associated with mastication to chew xeric‐adapted plants and to dig through hard soil types, whereas mesic populations excavate through soft, looser soil and may make use of their front limbs to aid the movement of soils when digging. Aridity influences the morphology of this species and could indicate the impact of environmental changes on speciation and mammalian skull morphology
Navigating Commitments: A Two-Country Game Theoretic Model Assessing Citizen Influence on IEA compliance
In this paper, we present an innovative approach that integrates machine learning and game theory into a game theoretic model involving two countries, incorporating predictive citizen influence. As part of the research, we carried out two surveys to assess citizens’ attitudes towards climate change, and whether these were persistent over time. Using a machine learning model, we attempt to predict people's attitudes towards environmental risk. Using the predictions as input into a game theoretic model, encompassing factors that influence whether a country will continue to comply with their commitments made in ratifying an International Environmental Agreement (IEA).
We explore the integration of machine learning predictions and game theory dynamics, providing insights into the potential and challenges of this interdisciplinary approach. Our findings reveal a significant discrepancy between the level of concern about environmental risk in the population and the sustained level of population concern required by the game theoretic model to influence governmental commitments Also, we delve into the reasons behind this discrepancy, and discuss potential strategies to mitigate the loss of focus on the need of societal changes to address the impact of climate change. The research presented is part of the broader research project investigating the engagement of citizens and NGOs to influence governments and intergovernmental bodies to uphold their commitments on climate change
Ethno-religious Minorities and Electoral Politics in Iran
The electoral politics of post-revolutionary Iran are often portrayed in Western media and academic analyses as an enduring battle between reform-oriented pragmatism and varying shades of conservatism. What is less well-covered is the experience of Iran’s ethnic and religious minorities in terms of their engagement with and experiences of electoral processes in the country. This article aims to advance understanding of political participation of ethnic and religious minorities and their place in the electoral system in Iran. The primary focus will be on presidential election turnout in three provinces which contain populations that are commonly understood to be largely distinct in both ethnic and religious terms from the Persian and Shi’i majority in the country – the largely Sunni provinces of Kurdistan, Sistan-Baluchistan and West Azerbaijan. The article uses data from official government sources, as well as interviews to highlight the local insights, to explore differences in election turnout in the three cases. In doing so, it illustrates the often stark differences between participation rates in these provinces compared to overall turnout. It also highlights how turnout has tended to peak around the rising popularity of reformist candidates, and underscores how participation tends to be influenced by the prominence of local leaders’ engagement with national electoral processes